31666897 has 2 divisors, whose sum is σ = 31666898. Its totient is φ = 31666896.

The previous prime is 31666891. The next prime is 31666909. The reversal of 31666897 is 79866613.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31348801 + 318096 = 5599^2 + 564^2 .

It is a cyclic number.

It is not a de Polignac number, because 31666897 - 2¹⁵ = 31634129 is a prime.

It is not a weakly prime, because it can be changed into another prime (31666891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15833448 + 15833449.

It is an arithmetic number, because the mean of its divisors is an integer number (15833449).

Almost surely, 2^31666897 is an apocalyptic number.

It is an amenable number.

31666897 is a deficient number, since it is larger than the sum of its proper divisors (1).

31666897 is an equidigital number, since it uses as much as digits as its factorization.

31666897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 326592, while the sum is 46.

The square root of 31666897 is about 5627.3348043279. The cubic root of 31666897 is about 316.3747656673.

The spelling of 31666897 in words is "thirty-one million, six hundred sixty-six thousand, eight hundred ninety-seven".