1645112401920 has 1792 divisors, whose sum is σ = 6848712622080. Its totient is φ = 370994577408.

The previous prime is 1645112401879. The next prime is 1645112401951. The reversal of 1645112401920 is 291042115461.

1645112401920 is a `hidden beast` number, since 1 + 6 + 451 + 12 + 4 + 0 + 192 + 0 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 12953640897 + ... + 12953641023.

It is an arithmetic number, because the mean of its divisors is an integer number (3821826240).

Almost surely, 2^{1645112401920} is an apocalyptic number.

1645112401920 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 1645112401920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3424356311040).

1645112401920 is an abundant number, since it is smaller than the sum of its proper divisors (5203600220160).

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

1645112401920 is a wasteful number, since it uses less digits than its factorization.

1645112401920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250 (or 220 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The spelling of 1645112401920 in words is "one trillion, six hundred forty-five billion, one hundred twelve million, four hundred one thousand, nine hundred twenty".