31912939 has 2 divisors, whose sum is σ = 31912940. Its totient is φ = 31912938.

The previous prime is 31912931. The next prime is 31912967. The reversal of 31912939 is 93921913.

It is a weak prime.

It is an emirp because it is prime and its reverse (93921913) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31912939 - 2³ = 31912931 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31912898 and 31912907.

It is not a weakly prime, because it can be changed into another prime (31912931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15956469 + 15956470.

It is an arithmetic number, because the mean of its divisors is an integer number (15956470).

Almost surely, 2^31912939 is an apocalyptic number.

31912939 is a deficient number, since it is larger than the sum of its proper divisors (1).

31912939 is an equidigital number, since it uses as much as digits as its factorization.

31912939 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13122, while the sum is 37.

The square root of 31912939 is about 5649.1538304422. The cubic root of 31912939 is about 317.1920307166.

The spelling of 31912939 in words is "thirty-one million, nine hundred twelve thousand, nine hundred thirty-nine".