31146391 has 2 divisors, whose sum is σ = 31146392. Its totient is φ = 31146390.

The previous prime is 31146389. The next prime is 31146407. The reversal of 31146391 is 19364113.

It is a weak prime.

It is an emirp because it is prime and its reverse (19364113) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31146391 - 2¹ = 31146389 is a prime.

Together with 31146389, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31146371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15573195 + 15573196.

It is an arithmetic number, because the mean of its divisors is an integer number (15573196).

Almost surely, 2^31146391 is an apocalyptic number.

31146391 is a deficient number, since it is larger than the sum of its proper divisors (1).

31146391 is an equidigital number, since it uses as much as digits as its factorization.

31146391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1944, while the sum is 28.

The square root of 31146391 is about 5580.8951790909. The cubic root of 31146391 is about 314.6317726247.

The spelling of 31146391 in words is "thirty-one million, one hundred forty-six thousand, three hundred ninety-one".