645759072 has 72 divisors (see below), whose sum is σ = 2098723536. Its totient is φ = 184502016.

The previous prime is 645759067. The next prime is 645759077. The reversal of 645759072 is 270957546.

645759072 is a `hidden beast` number, since 6 + 4 + 57 + 590 + 7 + 2 = 666.

It is an interprime number because it is at equal distance from previous prime (645759067) and next prime (645759077).

It is a tau number, because it is divible by the number of its divisors (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645759077) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 158143 + ... + 162174.

It is an arithmetic number, because the mean of its divisors is an integer number (29148938).

Almost surely, 2^645759072 is an apocalyptic number.

It is an amenable number.

645759072 is an abundant number, since it is smaller than the sum of its proper divisors (1452964464).

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

645759072 is a wasteful number, since it uses less digits than its factorization.

645759072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320340 (or 320329 counting only the distinct ones).

The product of its (nonzero) digits is 529200, while the sum is 45.

The square root of 645759072 is about 25411.7900195952. The cubic root of 645759072 is about 864.3510661809.

The spelling of 645759072 in words is "six hundred forty-five million, seven hundred fifty-nine thousand, seventy-two".