645839911332 has 96 divisors (see below), whose sum is σ = 2087563376640. Its totient is φ = 167750624160.

The previous prime is 645839911279. The next prime is 645839911351. The reversal of 645839911332 is 233119938546.

645839911332 is a `hidden beast` number, since 64 + 58 + 399 + 113 + 32 = 666.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 38822848 + ... + 38839479.

It is an arithmetic number, because the mean of its divisors is an integer number (21745451840).

Almost surely, 2^645839911332 is an apocalyptic number.

It is an amenable number.

645839911332 is an abundant number, since it is smaller than the sum of its proper divisors (1441723465308).

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

645839911332 is a wasteful number, since it uses less digits than its factorization.

645839911332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77662358 (or 77662350 counting only the distinct ones).

The product of its digits is 4199040, while the sum is 54.

The spelling of 645839911332 in words is "six hundred forty-five billion, eight hundred thirty-nine million, nine hundred eleven thousand, three hundred thirty-two".