31890407 has 2 divisors, whose sum is σ = 31890408. Its totient is φ = 31890406.

The previous prime is 31890389. The next prime is 31890473. The reversal of 31890407 is 70409813.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31890407 - 2²² = 27696103 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31895407) 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, 15945203 + 15945204.

It is an arithmetic number, because the mean of its divisors is an integer number (15945204).

Almost surely, 2^31890407 is an apocalyptic number.

31890407 is a deficient number, since it is larger than the sum of its proper divisors (1).

31890407 is an equidigital number, since it uses as much as digits as its factorization.

31890407 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 31890407 is about 5647.1591973310. The cubic root of 31890407 is about 317.1173624289.

The spelling of 31890407 in words is "thirty-one million, eight hundred ninety thousand, four hundred seven".