521648645 has 16 divisors (see below), whose sum is σ = 716802048. Its totient is φ = 357002880.

The previous prime is 521648639. The next prime is 521648651. The reversal of 521648645 is 546846125.

It is an interprime number because it is at equal distance from previous prime (521648639) and next prime (521648651).

It is not a de Polignac number, because 521648645 - 2⁶ = 521648581 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3932 + ... + 32538.

It is an arithmetic number, because the mean of its divisors is an integer number (44800128).

Almost surely, 2^521648645 is an apocalyptic number.

It is an amenable number.

521648645 is a deficient number, since it is larger than the sum of its proper divisors (195153403).

521648645 is a wasteful number, since it uses less digits than its factorization.

521648645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29140.

The product of its digits is 230400, while the sum is 41.

The square root of 521648645 is about 22839.6288279823. The cubic root of 521648645 is about 804.9940948347.

The spelling of 521648645 in words is "five hundred twenty-one million, six hundred forty-eight thousand, six hundred forty-five".