31530979 has 2 divisors, whose sum is σ = 31530980. Its totient is φ = 31530978.

The previous prime is 31530977. The next prime is 31531001. The reversal of 31530979 is 97903513.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31530979 - 2¹ = 31530977 is a prime.

Together with 31530977, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31530973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15765489 + 15765490.

It is an arithmetic number, because the mean of its divisors is an integer number (15765490).

Almost surely, 2^31530979 is an apocalyptic number.

31530979 is a deficient number, since it is larger than the sum of its proper divisors (1).

31530979 is an equidigital number, since it uses as much as digits as its factorization.

31530979 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 25515, while the sum is 37.

The square root of 31530979 is about 5615.2452306199. The cubic root of 31530979 is about 315.9214774452.

The spelling of 31530979 in words is "thirty-one million, five hundred thirty thousand, nine hundred seventy-nine".