91006998565 has 24 divisors (see below), whose sum is σ = 127422256032. Its totient is φ = 62216209440.

The previous prime is 91006998553. The next prime is 91006998583. The reversal of 91006998565 is 56589960019.

It is not a de Polignac number, because 91006998565 - 2⁹ = 91006998053 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 480019 + ... + 642208.

It is an arithmetic number, because the mean of its divisors is an integer number (5309260668).

Almost surely, 2^91006998565 is an apocalyptic number.

It is an amenable number.

91006998565 is a deficient number, since it is larger than the sum of its proper divisors (36415257467).

91006998565 is a wasteful number, since it uses less digits than its factorization.

91006998565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1122577 (or 1122570 counting only the distinct ones).

The product of its (nonzero) digits is 5248800, while the sum is 58.

The spelling of 91006998565 in words is "ninety-one billion, six million, nine hundred ninety-eight thousand, five hundred sixty-five".