645531004957 has 8 divisors (see below), whose sum is σ = 648194391000. Its totient is φ = 642870014784.

The previous prime is 645531004933. The next prime is 645531004981. The reversal of 645531004957 is 759400135546.

It is an interprime number because it is at equal distance from previous prime (645531004933) and next prime (645531004981).

It can be written as a sum of positive squares in 4 ways, for example, as 133477699716 + 512053305241 = 365346^2 + 715579^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 645531004957 - 2³⁹ = 95775191069 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 645531004957.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645531004927) 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, 57982 + ... + 1137727.

It is an arithmetic number, because the mean of its divisors is an integer number (81024298875).

Almost surely, 2^645531004957 is an apocalyptic number.

It is an amenable number.

645531004957 is a deficient number, since it is larger than the sum of its proper divisors (2663386043).

645531004957 is a wasteful number, since it uses less digits than its factorization.

645531004957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1197935.

The product of its (nonzero) digits is 2268000, while the sum is 49.

The spelling of 645531004957 in words is "six hundred forty-five billion, five hundred thirty-one million, four thousand, nine hundred fifty-seven".