31365421 has 2 divisors, whose sum is σ = 31365422. Its totient is φ = 31365420.

The previous prime is 31365413. The next prime is 31365431. The reversal of 31365421 is 12456313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20376196 + 10989225 = 4514^2 + 3315^2 .

It is a cyclic number.

It is not a de Polignac number, because 31365421 - 2³ = 31365413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31365401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15682710 + 15682711.

It is an arithmetic number, because the mean of its divisors is an integer number (15682711).

Almost surely, 2^31365421 is an apocalyptic number.

It is an amenable number.

31365421 is a deficient number, since it is larger than the sum of its proper divisors (1).

31365421 is an equidigital number, since it uses as much as digits as its factorization.

31365421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2160, while the sum is 25.

The square root of 31365421 is about 5600.4839969417. The cubic root of 31365421 is about 315.3675762801.

The spelling of 31365421 in words is "thirty-one million, three hundred sixty-five thousand, four hundred twenty-one".