31220923 has 2 divisors, whose sum is σ = 31220924. Its totient is φ = 31220922.

The previous prime is 31220909. The next prime is 31220927. The reversal of 31220923 is 32902213.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31220923 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31220894 and 31220903.

It is not a weakly prime, because it can be changed into another prime (31220927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15610461 + 15610462.

It is an arithmetic number, because the mean of its divisors is an integer number (15610462).

Almost surely, 2^31220923 is an apocalyptic number.

31220923 is a deficient number, since it is larger than the sum of its proper divisors (1).

31220923 is an equidigital number, since it uses as much as digits as its factorization.

31220923 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 22.

The square root of 31220923 is about 5587.5686125541. The cubic root of 31220923 is about 314.8825395599.

The spelling of 31220923 in words is "thirty-one million, two hundred twenty thousand, nine hundred twenty-three".