265161171991 has 2 divisors, whose sum is σ = 265161171992. Its totient is φ = 265161171990.

The previous prime is 265161171953. The next prime is 265161172037. The reversal of 265161171991 is 199171161562.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 265161171991 - 2²⁹ = 264624301079 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (265161171911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 132580585995 + 132580585996.

It is an arithmetic number, because the mean of its divisors is an integer number (132580585996).

Almost surely, 2^265161171991 is an apocalyptic number.

265161171991 is a deficient number, since it is larger than the sum of its proper divisors (1).

265161171991 is an equidigital number, since it uses as much as digits as its factorization.

265161171991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 204120, while the sum is 49.

The spelling of 265161171991 in words is "two hundred sixty-five billion, one hundred sixty-one million, one hundred seventy-one thousand, nine hundred ninety-one".