220991331 has 8 divisors (see below), whose sum is σ = 321441984. Its totient is φ = 133934120.

The previous prime is 220991311. The next prime is 220991357. The reversal of 220991331 is 133199022.

It is a happy number.

220991331 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 220991331 - 2¹⁴ = 220974947 is a prime.

It is a super-2 number, since 2×220991331² = 97674336754303122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (220991311) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3348321 + ... + 3348386.

It is an arithmetic number, because the mean of its divisors is an integer number (40180248).

Almost surely, 2^220991331 is an apocalyptic number.

220991331 is a deficient number, since it is larger than the sum of its proper divisors (100450653).

220991331 is a wasteful number, since it uses less digits than its factorization.

220991331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6696721.

The product of its (nonzero) digits is 2916, while the sum is 30.

The square root of 220991331 is about 14865.7771744366. Note that the first 3 decimals coincide. The cubic root of 220991331 is about 604.5864541759.

The spelling of 220991331 in words is "two hundred twenty million, nine hundred ninety-one thousand, three hundred thirty-one".