31591021201 has 2 divisors, whose sum is σ = 31591021202. Its totient is φ = 31591021200.

The previous prime is 31591021139. The next prime is 31591021219. The reversal of 31591021201 is 10212019513.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21018040576 + 10572980625 = 144976^2 + 102825^2 .

It is a cyclic number.

It is not a de Polignac number, because 31591021201 - 2⁷ = 31591021073 is a prime.

It is not a weakly prime, because it can be changed into another prime (31591025201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15795510600 + 15795510601.

It is an arithmetic number, because the mean of its divisors is an integer number (15795510601).

Almost surely, 2^31591021201 is an apocalyptic number.

It is an amenable number.

31591021201 is a deficient number, since it is larger than the sum of its proper divisors (1).

31591021201 is an equidigital number, since it uses as much as digits as its factorization.

31591021201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 540, while the sum is 25.

The spelling of 31591021201 in words is "thirty-one billion, five hundred ninety-one million, twenty-one thousand, two hundred one".