20221531 has 16 divisors (see below), whose sum is σ = 23182848. Its totient is φ = 17459200.

The previous prime is 20221489. The next prime is 20221541. The reversal of 20221531 is 13512202.

It is not a de Polignac number, because 20221531 - 2⁷ = 20221403 is a prime.

It is a super-2 number, since 2×20221531² = 817820631967922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20221541) 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 15 ways as a sum of consecutive naturals, for example, 64866 + ... + 65176.

It is an arithmetic number, because the mean of its divisors is an integer number (1448928).

Almost surely, 2^20221531 is an apocalyptic number.

20221531 is a deficient number, since it is larger than the sum of its proper divisors (2961317).

20221531 is a wasteful number, since it uses less digits than its factorization.

20221531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 602.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 20221531 is about 4496.8356652206. The cubic root of 20221531 is about 272.4402966585.

Adding to 20221531 its reverse (13512202), we get a palindrome (33733733).

It can be divided in two parts, 2022 and 1531, that added together give a palindrome (3553).

The spelling of 20221531 in words is "twenty million, two hundred twenty-one thousand, five hundred thirty-one".