23155521 has 8 divisors (see below), whose sum is σ = 31003104. Its totient is φ = 15372480.

The previous prime is 23155519. The next prime is 23155523. The reversal of 23155521 is 12555132.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (23155519) and next prime (23155523).

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

It is not a de Polignac number, because 23155521 - 2¹ = 23155519 is a prime.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 23155491 and 23155500.

It is not an unprimeable number, because it can be changed into a prime (23155523) 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, 15291 + ... + 16736.

It is an arithmetic number, because the mean of its divisors is an integer number (3875388).

Almost surely, 2^23155521 is an apocalyptic number.

It is an amenable number.

23155521 is a deficient number, since it is larger than the sum of its proper divisors (7847583).

23155521 is a wasteful number, since it uses less digits than its factorization.

23155521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32271.

The product of its digits is 1500, while the sum is 24.

The square root of 23155521 is about 4812.0183914861. The cubic root of 23155521 is about 285.0262456593.

The spelling of 23155521 in words is "twenty-three million, one hundred fifty-five thousand, five hundred twenty-one".