645131008 has 36 divisors (see below), whose sum is σ = 1290156448. Its totient is φ = 321960960.

The previous prime is 645130991. The next prime is 645131051. The reversal of 645131008 is 800131546.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 154873 + ... + 158983.

Almost surely, 2^645131008 is an apocalyptic number.

It is an amenable number.

645131008 is a deficient number, since it is larger than the sum of its proper divisors (645025440).

645131008 is an equidigital number, since it uses as much as digits as its factorization.

645131008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4740 (or 4726 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 645131008 is about 25399.4292849269. The cubic root of 645131008 is about 864.0707532365.

The spelling of 645131008 in words is "six hundred forty-five million, one hundred thirty-one thousand, eight".