645451506304 has 64 divisors (see below), whose sum is σ = 1402913793600. Its totient is φ = 293354219520.

The previous prime is 645451506283. The next prime is 645451506307. The reversal of 645451506304 is 403605154546.

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (645451506307) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16210132 + ... + 16249900.

It is an arithmetic number, because the mean of its divisors is an integer number (21920528025).

Almost surely, 2^645451506304 is an apocalyptic number.

645451506304 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

645451506304 is an abundant number, since it is smaller than the sum of its proper divisors (757462287296).

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

645451506304 is a wasteful number, since it uses less digits than its factorization.

645451506304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51321 (or 51309 counting only the distinct ones).

The product of its (nonzero) digits is 864000, while the sum is 43.

The spelling of 645451506304 in words is "six hundred forty-five billion, four hundred fifty-one million, five hundred six thousand, three hundred four".