31320929 has 2 divisors, whose sum is σ = 31320930. Its totient is φ = 31320928.

The previous prime is 31320889. The next prime is 31320931. The reversal of 31320929 is 92902313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24482704 + 6838225 = 4948^2 + 2615^2 .

It is a cyclic number.

It is not a de Polignac number, because 31320929 - 2¹² = 31316833 is a prime.

Together with 31320931, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (31320229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15660464 + 15660465.

It is an arithmetic number, because the mean of its divisors is an integer number (15660465).

Almost surely, 2^31320929 is an apocalyptic number.

It is an amenable number.

31320929 is a deficient number, since it is larger than the sum of its proper divisors (1).

31320929 is an equidigital number, since it uses as much as digits as its factorization.

31320929 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2916, while the sum is 29.

The square root of 31320929 is about 5596.5104306166. The cubic root of 31320929 is about 315.2183889108.

The spelling of 31320929 in words is "thirty-one million, three hundred twenty thousand, nine hundred twenty-nine".