645421537250 has 64 divisors (see below), whose sum is σ = 1394505275904. Its totient is φ = 219096360000.

The previous prime is 645421537249. The next prime is 645421537261. The reversal of 645421537250 is 52735124546.

645421537250 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (44) coincides with the sum of the digits of its distinct prime factors.

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, 1649054 + ... + 2002553.

It is an arithmetic number, because the mean of its divisors is an integer number (21789144936).

Almost surely, 2^645421537250 is an apocalyptic number.

645421537250 is an abundant number, since it is smaller than the sum of its proper divisors (749083738654).

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

645421537250 is a wasteful number, since it uses less digits than its factorization.

645421537250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3651732 (or 3651722 counting only the distinct ones).

The product of its (nonzero) digits is 1008000, while the sum is 44.

The spelling of 645421537250 in words is "six hundred forty-five billion, four hundred twenty-one million, five hundred thirty-seven thousand, two hundred fifty".