645624432016 has 40 divisors (see below), whose sum is σ = 1316985350400. Its totient is φ = 305763730560.

The previous prime is 645624431999. The next prime is 645624432059. The reversal of 645624432016 is 610234426546.

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1413921 + ... + 1813951.

It is an arithmetic number, because the mean of its divisors is an integer number (32924633760).

Almost surely, 2^645624432016 is an apocalyptic number.

It is an amenable number.

645624432016 is an abundant number, since it is smaller than the sum of its proper divisors (671360918384).

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

645624432016 is a wasteful number, since it uses less digits than its factorization.

645624432016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 405367 (or 405361 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 43.

The spelling of 645624432016 in words is "six hundred forty-five billion, six hundred twenty-four million, four hundred thirty-two thousand, sixteen".