523617921 has 12 divisors (see below), whose sum is σ = 756535780. Its totient is φ = 348986880.

The previous prime is 523617893. The next prime is 523617967. The reversal of 523617921 is 129716325.

523617921 is a `hidden beast` number, since 523 + 61 + 79 + 2 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 262440000 + 261177921 = 16200^2 + 16161^2 .

It is not a de Polignac number, because 523617921 - 2¹⁰ = 523616897 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (523617121) 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, 60081 + ... + 68241.

Almost surely, 2^523617921 is an apocalyptic number.

It is an amenable number.

523617921 is a deficient number, since it is larger than the sum of its proper divisors (232917859).

523617921 is a wasteful number, since it uses less digits than its factorization.

523617921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15296 (or 15293 counting only the distinct ones).

The product of its digits is 22680, while the sum is 36.

The square root of 523617921 is about 22882.6991633417. The cubic root of 523617921 is about 806.0058006425.

The spelling of 523617921 in words is "five hundred twenty-three million, six hundred seventeen thousand, nine hundred twenty-one".