265659991 has 2 divisors, whose sum is σ = 265659992. Its totient is φ = 265659990.

The previous prime is 265659983. The next prime is 265660007. The reversal of 265659991 is 199956562.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 265659991 - 2³ = 265659983 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (265659971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 132829995 + 132829996.

It is an arithmetic number, because the mean of its divisors is an integer number (132829996).

Almost surely, 2^265659991 is an apocalyptic number.

265659991 is a deficient number, since it is larger than the sum of its proper divisors (1).

265659991 is an equidigital number, since it uses as much as digits as its factorization.

265659991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1312200, while the sum is 52.

The square root of 265659991 is about 16299.0794525335. The cubic root of 265659991 is about 642.8486228453.

The spelling of 265659991 in words is "two hundred sixty-five million, six hundred fifty-nine thousand, nine hundred ninety-one".