31268221 has 2 divisors, whose sum is σ = 31268222. Its totient is φ = 31268220.

The previous prime is 31268203. The next prime is 31268231. The reversal of 31268221 is 12286213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23145721 + 8122500 = 4811^2 + 2850^2 .

It is a cyclic number.

It is not a de Polignac number, because 31268221 - 2⁷ = 31268093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31268231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15634110 + 15634111.

It is an arithmetic number, because the mean of its divisors is an integer number (15634111).

Almost surely, 2^31268221 is an apocalyptic number.

It is an amenable number.

31268221 is a deficient number, since it is larger than the sum of its proper divisors (1).

31268221 is an equidigital number, since it uses as much as digits as its factorization.

31268221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152, while the sum is 25.

The square root of 31268221 is about 5591.7994420401. The cubic root of 31268221 is about 315.0414693031.

The spelling of 31268221 in words is "thirty-one million, two hundred sixty-eight thousand, two hundred twenty-one".