21131013097 has 2 divisors, whose sum is σ = 21131013098. Its totient is φ = 21131013096.

The previous prime is 21131013061. The next prime is 21131013161. The reversal of 21131013097 is 79031013112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18346973401 + 2784039696 = 135451^2 + 52764^2 .

It is a cyclic number.

It is not a de Polignac number, because 21131013097 - 2¹¹ = 21131011049 is a prime.

It is not a weakly prime, because it can be changed into another prime (21131013037) 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, 10565506548 + 10565506549.

It is an arithmetic number, because the mean of its divisors is an integer number (10565506549).

Almost surely, 2^21131013097 is an apocalyptic number.

It is an amenable number.

21131013097 is a deficient number, since it is larger than the sum of its proper divisors (1).

21131013097 is an equidigital number, since it uses as much as digits as its factorization.

21131013097 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1134, while the sum is 28.

The spelling of 21131013097 in words is "twenty-one billion, one hundred thirty-one million, thirteen thousand, ninety-seven".