220031291 has 2 divisors, whose sum is σ = 220031292. Its totient is φ = 220031290.

The previous prime is 220031281. The next prime is 220031303. The reversal of 220031291 is 192130022.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-220031291 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is equal to p_12124154 and since 220031291 and 12124154 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (220031281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110015645 + 110015646.

It is an arithmetic number, because the mean of its divisors is an integer number (110015646).

Almost surely, 2^220031291 is an apocalyptic number.

220031291 is a deficient number, since it is larger than the sum of its proper divisors (1).

220031291 is an equidigital number, since it uses as much as digits as its factorization.

220031291 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 220031291 is about 14833.4517560816. The cubic root of 220031291 is about 603.7096932085.

The spelling of 220031291 in words is "two hundred twenty million, thirty-one thousand, two hundred ninety-one".