31391073 has 12 divisors (see below), whose sum is σ = 51820288. Its totient is φ = 17937720.

The previous prime is 31391071. The next prime is 31391077. The reversal of 31391073 is 37019313.

It is not a de Polignac number, because 31391073 - 2¹ = 31391071 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31391071) 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 in 11 ways as a sum of consecutive naturals, for example, 249073 + ... + 249198.

Almost surely, 2^31391073 is an apocalyptic number.

It is an amenable number.

31391073 is a deficient number, since it is larger than the sum of its proper divisors (20429215).

31391073 is a wasteful number, since it uses less digits than its factorization.

31391073 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 498284 (or 498281 counting only the distinct ones).

The product of its (nonzero) digits is 1701, while the sum is 27.

The square root of 31391073 is about 5602.7736880941. The cubic root of 31391073 is about 315.4535266082.

The spelling of 31391073 in words is "thirty-one million, three hundred ninety-one thousand, seventy-three".