23215665 has 24 divisors (see below), whose sum is σ = 40832064. Its totient is φ = 11255200.

The previous prime is 23215597. The next prime is 23215667. The reversal of 23215665 is 56651232.

It is not a de Polignac number, because 23215665 - 2¹⁶ = 23150129 is a prime.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (23215667) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4581 + ... + 8210.

It is an arithmetic number, because the mean of its divisors is an integer number (1701336).

Almost surely, 2^23215665 is an apocalyptic number.

It is an amenable number.

23215665 is a deficient number, since it is larger than the sum of its proper divisors (17616399).

23215665 is a wasteful number, since it uses less digits than its factorization.

23215665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12821 (or 12810 counting only the distinct ones).

The product of its digits is 10800, while the sum is 30.

The square root of 23215665 is about 4818.2636914142. The cubic root of 23215665 is about 285.2728074167.

Adding to 23215665 its reverse (56651232), we get a palindrome (79866897).

It can be divided in two parts, 232156 and 65, that added together give a triangular number (232221 = T₆₈₁).

The spelling of 23215665 in words is "twenty-three million, two hundred fifteen thousand, six hundred sixty-five".