31047997 has 2 divisors, whose sum is σ = 31047998. Its totient is φ = 31047996.

The previous prime is 31047979. The next prime is 31048037. The reversal of 31047997 is 79974013.

Together with previous prime (31047979) it forms an Ormiston pair, because they use the same digits, order apart.

It is an a-pointer prime, because the next prime (31048037) can be obtained adding 31047997 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29746116 + 1301881 = 5454^2 + 1141^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31047997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31047977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15523998 + 15523999.

It is an arithmetic number, because the mean of its divisors is an integer number (15523999).

Almost surely, 2^31047997 is an apocalyptic number.

It is an amenable number.

31047997 is a deficient number, since it is larger than the sum of its proper divisors (1).

31047997 is an equidigital number, since it uses as much as digits as its factorization.

31047997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 47628, while the sum is 40.

The square root of 31047997 is about 5572.0729535784. The cubic root of 31047997 is about 314.3001072806.

The spelling of 31047997 in words is "thirty-one million, forty-seven thousand, nine hundred ninety-seven".