22520987 has 4 divisors (see below), whose sum is σ = 22838256. Its totient is φ = 22203720.

The previous prime is 22520969. The next prime is 22520989. The reversal of 22520987 is 78902522.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78902522 = 2 ⋅39451261.

It is a cyclic number.

It is not a de Polignac number, because 22520987 - 2⁶ = 22520923 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22520989) 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, 158528 + ... + 158669.

It is an arithmetic number, because the mean of its divisors is an integer number (5709564).

Almost surely, 2^22520987 is an apocalyptic number.

22520987 is a deficient number, since it is larger than the sum of its proper divisors (317269).

22520987 is an equidigital number, since it uses as much as digits as its factorization.

22520987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317268.

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 22520987 is about 4745.6281986687. The cubic root of 22520987 is about 282.3985570458.

It can be divided in two parts, 225 and 20987, that added together give a palindrome (21212).

The spelling of 22520987 in words is "twenty-two million, five hundred twenty thousand, nine hundred eighty-seven".