22521457 has 4 divisors (see below), whose sum is σ = 25738816. Its totient is φ = 19304100.

The previous prime is 22521451. The next prime is 22521461. The reversal of 22521457 is 75412522.

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 a cyclic number.

It is not a de Polignac number, because 22521457 - 2⁷ = 22521329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22521451) 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, 1608669 + ... + 1608682.

It is an arithmetic number, because the mean of its divisors is an integer number (6434704).

Almost surely, 2^22521457 is an apocalyptic number.

It is an amenable number.

22521457 is a deficient number, since it is larger than the sum of its proper divisors (3217359).

22521457 is an equidigital number, since it uses as much as digits as its factorization.

22521457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3217358.

The product of its digits is 5600, while the sum is 28.

The square root of 22521457 is about 4745.6777176711. The cubic root of 22521457 is about 282.4005215304.

Adding to 22521457 its reverse (75412522), we get a palindrome (97933979).

The spelling of 22521457 in words is "twenty-two million, five hundred twenty-one thousand, four hundred fifty-seven".