23531521 has 8 divisors (see below), whose sum is σ = 25604264. Its totient is φ = 21496320.

The previous prime is 23531513. The next prime is 23531527. The reversal of 23531521 is 12513532.

It can be written as a sum of positive squares in 4 ways, for example, as 115600 + 23415921 = 340^2 + 4839^2 .

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 23531521 - 2³ = 23531513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 23531492 and 23531501.

It is not an unprimeable number, because it can be changed into a prime (23531527) 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, 8070 + ... + 10591.

It is an arithmetic number, because the mean of its divisors is an integer number (3200533).

Almost surely, 2^23531521 is an apocalyptic number.

It is an amenable number.

23531521 is a deficient number, since it is larger than the sum of its proper divisors (2072743).

23531521 is a wasteful number, since it uses less digits than its factorization.

23531521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18771.

The product of its digits is 900, while the sum is 22.

The square root of 23531521 is about 4850.9299108521. The cubic root of 23531521 is about 286.5607244782.

The spelling of 23531521 in words is "twenty-three million, five hundred thirty-one thousand, five hundred twenty-one".