645722372 has 24 divisors (see below), whose sum is σ = 1221642240. Its totient is φ = 297600480.

The previous prime is 645722359. The next prime is 645722377. The reversal of 645722372 is 273227546.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is not an unprimeable number, because it can be changed into a prime (645722377) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 112004 + ... + 117627.

It is an arithmetic number, because the mean of its divisors is an integer number (50901760).

Almost surely, 2^645722372 is an apocalyptic number.

It is an amenable number.

645722372 is a deficient number, since it is larger than the sum of its proper divisors (575919868).

645722372 is a wasteful number, since it uses less digits than its factorization.

645722372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229691 (or 229689 counting only the distinct ones).

The product of its digits is 141120, while the sum is 38.

The square root of 645722372 is about 25411.0679035730. The cubic root of 645722372 is about 864.3346915057.

The spelling of 645722372 in words is "six hundred forty-five million, seven hundred twenty-two thousand, three hundred seventy-two".