31220797 has 2 divisors, whose sum is σ = 31220798. Its totient is φ = 31220796.

The previous prime is 31220779. The next prime is 31220801. The reversal of 31220797 is 79702213.

Together with previous prime (31220779) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31069476 + 151321 = 5574^2 + 389^2 .

It is a cyclic number.

It is not a de Polignac number, because 31220797 - 2²³ = 22832189 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31220747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15610398 + 15610399.

It is an arithmetic number, because the mean of its divisors is an integer number (15610399).

Almost surely, 2^31220797 is an apocalyptic number.

It is an amenable number.

31220797 is a deficient number, since it is larger than the sum of its proper divisors (1).

31220797 is an equidigital number, since it uses as much as digits as its factorization.

31220797 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5292, while the sum is 31.

The square root of 31220797 is about 5587.5573375134. The cubic root of 31220797 is about 314.8821159631.

The spelling of 31220797 in words is "thirty-one million, two hundred twenty thousand, seven hundred ninety-seven".