26138431217 has 2 divisors, whose sum is σ = 26138431218. Its totient is φ = 26138431216.

The previous prime is 26138431181. The next prime is 26138431229. The reversal of 26138431217 is 71213483162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14145772096 + 11992659121 = 118936^2 + 109511^2 .

It is a cyclic number.

It is not a de Polignac number, because 26138431217 - 2⁸ = 26138430961 is a prime.

It is not a weakly prime, because it can be changed into another prime (26138431247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13069215608 + 13069215609.

It is an arithmetic number, because the mean of its divisors is an integer number (13069215609).

Almost surely, 2^26138431217 is an apocalyptic number.

It is an amenable number.

26138431217 is a deficient number, since it is larger than the sum of its proper divisors (1).

26138431217 is an equidigital number, since it uses as much as digits as its factorization.

26138431217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48384, while the sum is 38.

The spelling of 26138431217 in words is "twenty-six billion, one hundred thirty-eight million, four hundred thirty-one thousand, two hundred seventeen".