31369021 has 2 divisors, whose sum is σ = 31369022. Its totient is φ = 31369020.

The previous prime is 31369003. The next prime is 31369043. The reversal of 31369021 is 12096313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17388900 + 13980121 = 4170^2 + 3739^2 .

It is a cyclic number.

It is not a de Polignac number, because 31369021 - 2⁹ = 31368509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31369321) 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, 15684510 + 15684511.

It is an arithmetic number, because the mean of its divisors is an integer number (15684511).

Almost surely, 2^31369021 is an apocalyptic number.

It is an amenable number.

31369021 is a deficient number, since it is larger than the sum of its proper divisors (1).

31369021 is an equidigital number, since it uses as much as digits as its factorization.

31369021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 31369021 is about 5600.8053885133. The cubic root of 31369021 is about 315.3796413697.

The spelling of 31369021 in words is "thirty-one million, three hundred sixty-nine thousand, twenty-one".