991723592265 has 192 divisors, whose sum is σ = 1975356979200. Its totient is φ = 423399005568.

The previous prime is 991723592263. The next prime is 991723592267. The reversal of 991723592265 is 562295327199.

It is an interprime number because it is at equal distance from previous prime (991723592263) and next prime (991723592267).

It is not a de Polignac number, because 991723592265 - 2¹ = 991723592263 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 991723592199 and 991723592208.

It is not an unprimeable number, because it can be changed into a prime (991723592263) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 384536746 + ... + 384539324.

It is an arithmetic number, because the mean of its divisors is an integer number (10288317600).

Almost surely, 2^991723592265 is an apocalyptic number.

It is an amenable number.

991723592265 is a deficient number, since it is larger than the sum of its proper divisors (983633386935).

991723592265 is a wasteful number, since it uses less digits than its factorization.

991723592265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2713 (or 2660 counting only the distinct ones).

The product of its digits is 18370800, while the sum is 60.

The spelling of 991723592265 in words is "nine hundred ninety-one billion, seven hundred twenty-three million, five hundred ninety-two thousand, two hundred sixty-five".