220585021 has 4 divisors (see below), whose sum is σ = 220738912. Its totient is φ = 220431132.

The previous prime is 220584997. The next prime is 220585031. The reversal of 220585021 is 120585022.

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 220585021 - 2⁵ = 220584989 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 (220585031) 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, 74775 + ... + 77668.

It is an arithmetic number, because the mean of its divisors is an integer number (55184728).

Almost surely, 2^220585021 is an apocalyptic number.

It is an amenable number.

220585021 is a deficient number, since it is larger than the sum of its proper divisors (153891).

220585021 is a wasteful number, since it uses less digits than its factorization.

220585021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153890.

The product of its (nonzero) digits is 1600, while the sum is 25.

The square root of 220585021 is about 14852.1049349915. The cubic root of 220585021 is about 604.2157002286.

Subtracting from 220585021 its reverse (120585022), we obtain a palindrome (99999999).

The spelling of 220585021 in words is "two hundred twenty million, five hundred eighty-five thousand, twenty-one".