645724002 has 64 divisors (see below), whose sum is σ = 1623564288. Its totient is φ = 167706000.

The previous prime is 645723977. The next prime is 645724003. The reversal of 645724002 is 200427546.

It is not an unprimeable number, because it can be changed into a prime (645724003) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 50127 + ... + 61677.

It is an arithmetic number, because the mean of its divisors is an integer number (25368192).

Almost surely, 2^645724002 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645724002, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (811782144).

645724002 is an abundant number, since it is smaller than the sum of its proper divisors (977840286).

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

645724002 is a wasteful number, since it uses less digits than its factorization.

645724002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11596 (or 11574 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 30.

The square root of 645724002 is about 25411.0999761915. The cubic root of 645724002 is about 864.3354187865.

The spelling of 645724002 in words is "six hundred forty-five million, seven hundred twenty-four thousand, two".