31222091 has 2 divisors, whose sum is σ = 31222092. Its totient is φ = 31222090.

The previous prime is 31222021. The next prime is 31222099. The reversal of 31222091 is 19022213.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 31222091 - 2¹⁸ = 30959947 is a prime.

It is not a weakly prime, because it can be changed into another prime (31222099) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15611045 + 15611046.

It is an arithmetic number, because the mean of its divisors is an integer number (15611046).

Almost surely, 2^31222091 is an apocalyptic number.

31222091 is a deficient number, since it is larger than the sum of its proper divisors (1).

31222091 is an equidigital number, since it uses as much as digits as its factorization.

31222091 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 31222091 is about 5587.6731293088. The cubic root of 31222091 is about 314.8864661812.

The spelling of 31222091 in words is "thirty-one million, two hundred twenty-two thousand, ninety-one".