31521666097 has 2 divisors, whose sum is σ = 31521666098. Its totient is φ = 31521666096.

The previous prime is 31521666089. The next prime is 31521666119. The reversal of 31521666097 is 79066612513.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31387082896 + 134583201 = 177164^2 + 11601^2 .

It is a cyclic number.

It is not a de Polignac number, because 31521666097 - 2³ = 31521666089 is a prime.

It is not a weakly prime, because it can be changed into another prime (31521666797) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15760833048 + 15760833049.

It is an arithmetic number, because the mean of its divisors is an integer number (15760833049).

Almost surely, 2^31521666097 is an apocalyptic number.

It is an amenable number.

31521666097 is a deficient number, since it is larger than the sum of its proper divisors (1).

31521666097 is an equidigital number, since it uses as much as digits as its factorization.

31521666097 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 408240, while the sum is 46.

The spelling of 31521666097 in words is "thirty-one billion, five hundred twenty-one million, six hundred sixty-six thousand, ninety-seven".