1643601600 has 252 divisors, whose sum is σ = 5887043344. Its totient is φ = 434903040.

The previous prime is 1643601581. The next prime is 1643601613. The reversal of 1643601600 is 61063461.

1643601600 is a `hidden beast` number, since 1 + 643 + 6 + 0 + 16 + 0 + 0 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 2260437 + ... + 2261163.

Almost surely, 2^1643601600 is an apocalyptic number.

1643601600 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1643601600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2943521672).

1643601600 is an abundant number, since it is smaller than the sum of its proper divisors (4243441744).

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

1643601600 is a wasteful number, since it uses less digits than its factorization.

1643601600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 912 (or 894 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 1643601600 is about 40541.3566620556. The cubic root of 1643601600 is about 1180.1363435293.

The spelling of 1643601600 in words is "one billion, six hundred forty-three million, six hundred one thousand, six hundred".