31399469 has 2 divisors, whose sum is σ = 31399470. Its totient is φ = 31399468.

The previous prime is 31399451. The next prime is 31399477. The reversal of 31399469 is 96499313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31214569 + 184900 = 5587^2 + 430^2 .

It is an emirp because it is prime and its reverse (96499313) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31399469 - 2⁸ = 31399213 is a prime.

It is a super-2 number, since 2×31399469² = 1971853306963922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31399429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15699734 + 15699735.

It is an arithmetic number, because the mean of its divisors is an integer number (15699735).

Almost surely, 2^31399469 is an apocalyptic number.

It is an amenable number.

31399469 is a deficient number, since it is larger than the sum of its proper divisors (1).

31399469 is an equidigital number, since it uses as much as digits as its factorization.

31399469 is an evil number, because the sum of its binary digits is even.

The product of its digits is 157464, while the sum is 44.

The square root of 31399469 is about 5603.5229097417. The cubic root of 31399469 is about 315.4816483156.

The spelling of 31399469 in words is "thirty-one million, three hundred ninety-nine thousand, four hundred sixty-nine".