31081097 has 2 divisors, whose sum is σ = 31081098. Its totient is φ = 31081096.

The previous prime is 31081021. The next prime is 31081103. The reversal of 31081097 is 79018013.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26666896 + 4414201 = 5164^2 + 2101^2 .

It is an emirp because it is prime and its reverse (79018013) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31081097 - 2¹⁶ = 31015561 is a prime.

It is a nialpdrome in base 9.

It is not a weakly prime, because it can be changed into another prime (31071097) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15540548 + 15540549.

It is an arithmetic number, because the mean of its divisors is an integer number (15540549).

Almost surely, 2^31081097 is an apocalyptic number.

It is an amenable number.

31081097 is a deficient number, since it is larger than the sum of its proper divisors (1).

31081097 is an equidigital number, since it uses as much as digits as its factorization.

31081097 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1512, while the sum is 29.

The square root of 31081097 is about 5575.0423316779. The cubic root of 31081097 is about 314.4117584850.

The spelling of 31081097 in words is "thirty-one million, eighty-one thousand, ninety-seven".