31319389 has 4 divisors (see below), whose sum is σ = 33161724. Its totient is φ = 29477056.

The previous prime is 31319381. The next prime is 31319411. The reversal of 31319389 is 98391313.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98391313 = 857 ⋅114809.

It can be written as a sum of positive squares in 2 ways, for example, as 25583364 + 5736025 = 5058^2 + 2395^2 .

It is a cyclic number.

It is not a de Polignac number, because 31319389 - 2³ = 31319381 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31319381) 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 3 ways as a sum of consecutive naturals, for example, 921142 + ... + 921175.

It is an arithmetic number, because the mean of its divisors is an integer number (8290431).

Almost surely, 2^31319389 is an apocalyptic number.

It is an amenable number.

31319389 is a deficient number, since it is larger than the sum of its proper divisors (1842335).

31319389 is a wasteful number, since it uses less digits than its factorization.

31319389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1842334.

The product of its digits is 17496, while the sum is 37.

The square root of 31319389 is about 5596.3728431905. The cubic root of 31319389 is about 315.2132225647.

The spelling of 31319389 in words is "thirty-one million, three hundred nineteen thousand, three hundred eighty-nine".