22515997 has 4 divisors (see below), whose sum is σ = 25732576. Its totient is φ = 19299420.

The previous prime is 22515989. The next prime is 22516001. The reversal of 22515997 is 79951522.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 22515997 - 2³ = 22515989 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 (22515797) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1608279 + ... + 1608292.

It is an arithmetic number, because the mean of its divisors is an integer number (6433144).

Almost surely, 2^22515997 is an apocalyptic number.

It is an amenable number.

22515997 is a deficient number, since it is larger than the sum of its proper divisors (3216579).

22515997 is an equidigital number, since it uses as much as digits as its factorization.

22515997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3216578.

The product of its digits is 56700, while the sum is 40.

The square root of 22515997 is about 4745.1024224984. The cubic root of 22515997 is about 282.3776983849.

The spelling of 22515997 in words is "twenty-two million, five hundred fifteen thousand, nine hundred ninety-seven".