12639601817 has 2 divisors, whose sum is σ = 12639601818. Its totient is φ = 12639601816.

The previous prime is 12639601789. The next prime is 12639601823. The reversal of 12639601817 is 71810693621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7611515536 + 5028086281 = 87244^2 + 70909^2 .

It is a cyclic number.

It is not a de Polignac number, because 12639601817 - 2¹⁴ = 12639585433 is a prime.

It is not a weakly prime, because it can be changed into another prime (12639603817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6319800908 + 6319800909.

It is an arithmetic number, because the mean of its divisors is an integer number (6319800909).

Almost surely, 2^12639601817 is an apocalyptic number.

It is an amenable number.

12639601817 is a deficient number, since it is larger than the sum of its proper divisors (1).

12639601817 is an equidigital number, since it uses as much as digits as its factorization.

12639601817 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108864, while the sum is 44.

The spelling of 12639601817 in words is "twelve billion, six hundred thirty-nine million, six hundred one thousand, eight hundred seventeen".