645156928 has 56 divisors (see below), whose sum is σ = 1391789952. Its totient is φ = 294941184.

The previous prime is 645156899. The next prime is 645156959. The reversal of 645156928 is 829651546.

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, 85401 + ... + 92647.

It is an arithmetic number, because the mean of its divisors is an integer number (24853392).

Almost surely, 2^645156928 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645156928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (695894976).

645156928 is an abundant number, since it is smaller than the sum of its proper divisors (746633024).

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

645156928 is a wasteful number, since it uses less digits than its factorization.

645156928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7379 (or 7369 counting only the distinct ones).

The product of its digits is 518400, while the sum is 46.

The square root of 645156928 is about 25399.9395274871. The cubic root of 645156928 is about 864.0823252602.

The spelling of 645156928 in words is "six hundred forty-five million, one hundred fifty-six thousand, nine hundred twenty-eight".