21293591129 has 2 divisors, whose sum is σ = 21293591130. Its totient is φ = 21293591128.

The previous prime is 21293591119. The next prime is 21293591141. The reversal of 21293591129 is 92119539212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14847909904 + 6445681225 = 121852^2 + 80285^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21293591129 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21293591129.

It is not a weakly prime, because it can be changed into another prime (21293591119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10646795564 + 10646795565.

It is an arithmetic number, because the mean of its divisors is an integer number (10646795565).

Almost surely, 2^21293591129 is an apocalyptic number.

It is an amenable number.

21293591129 is a deficient number, since it is larger than the sum of its proper divisors (1).

21293591129 is an equidigital number, since it uses as much as digits as its factorization.

21293591129 is an evil number, because the sum of its binary digits is even.

The product of its digits is 87480, while the sum is 44.

The spelling of 21293591129 in words is "twenty-one billion, two hundred ninety-three million, five hundred ninety-one thousand, one hundred twenty-nine".