645587688 has 16 divisors (see below), whose sum is σ = 1613969280. Its totient is φ = 215195888.

The previous prime is 645587669. The next prime is 645587689. The reversal of 645587688 is 886785546.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (645587689) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13449720 + ... + 13449767.

It is an arithmetic number, because the mean of its divisors is an integer number (100873080).

Almost surely, 2^645587688 is an apocalyptic number.

It is an amenable number.

645587688 is an abundant number, since it is smaller than the sum of its proper divisors (968381592).

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

645587688 is a wasteful number, since it uses less digits than its factorization.

645587688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26899496 (or 26899492 counting only the distinct ones).

The product of its digits is 12902400, while the sum is 57.

The square root of 645587688 is about 25408.4176602952. The cubic root of 645587688 is about 864.2745933618.

The spelling of 645587688 in words is "six hundred forty-five million, five hundred eighty-seven thousand, six hundred eighty-eight".