23015557 has 4 divisors (see below), whose sum is σ = 23027116. Its totient is φ = 23004000.

The previous prime is 23015549. The next prime is 23015561. The reversal of 23015557 is 75551032.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 6806881 + 16208676 = 2609^2 + 4026^2 .

It is a cyclic number.

It is not a de Polignac number, because 23015557 - 2³ = 23015549 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23015537) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1944 + ... + 7057.

It is an arithmetic number, because the mean of its divisors is an integer number (5756779).

Almost surely, 2^23015557 is an apocalyptic number.

It is an amenable number.

23015557 is a deficient number, since it is larger than the sum of its proper divisors (11559).

23015557 is an equidigital number, since it uses as much as digits as its factorization.

23015557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11558.

The product of its (nonzero) digits is 5250, while the sum is 28.

The square root of 23015557 is about 4797.4531785104. The cubic root of 23015557 is about 284.4508024306.

Adding to 23015557 its reverse (75551032), we get a palindrome (98566589).

The spelling of 23015557 in words is "twenty-three million, fifteen thousand, five hundred fifty-seven".