1645037108100 has 135 divisors (see below), whose sum is σ = 5332934628021. Its totient is φ = 438645780000.

The previous prime is 1645037108093. The next prime is 1645037108101. The reversal of 1645037108100 is 18017305461.

The square root of 1645037108100 is 1282590.

It is a perfect power (a square), and thus also a powerful number.

1645037108100 is a `hidden beast` number, since 1 + 6 + 4 + 503 + 71 + 0 + 81 + 0 + 0 = 666.

It can be written as a sum of positive squares in only one way, i.e., 592213358916 + 1052823749184 = 769554^2 + 1026072^2 .

It is a tau number, because it is divible by the number of its divisors (135).

It is a super-2 number, since 2×1645037108100² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (1645037108101) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 115425975 + ... + 115440225.

Almost surely, 2^{1645037108100} is an apocalyptic number.

1645037108100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1645037108100 is the 1282590-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1645037108100

1645037108100 is an abundant number, since it is smaller than the sum of its proper divisors (3687897519921).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1645037108100 is an frugal number, since it uses more digits than its factorization.

1645037108100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28528 (or 14261 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

Multiplying 1645037108100 by its sum of digits (36), we get a square (59221335891600 = 7695540²).

1645037108100 divided by its sum of digits (36) gives a square (45695475225 = 213765²).

The spelling of 1645037108100 in words is "one trillion, six hundred forty-five billion, thirty-seven million, one hundred eight thousand, one hundred".