991724604605 has 24 divisors (see below), whose sum is σ = 1384425570528. Its totient is φ = 680010756768.

The previous prime is 991724604551. The next prime is 991724604677. The reversal of 991724604605 is 506406427199.

It is a de Polignac number, because none of the positive numbers 2^k-991724604605 is a prime.

It is a super-4 number, since 4×991724604605⁴ (a number of 49 digits) contains 4444 as substring.

It is a hoax number, since the sum of its digits (53) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6794402 + ... + 6938828.

It is an arithmetic number, because the mean of its divisors is an integer number (57684398772).

Almost surely, 2^991724604605 is an apocalyptic number.

It is an amenable number.

991724604605 is a deficient number, since it is larger than the sum of its proper divisors (392700965923).

991724604605 is a wasteful number, since it uses less digits than its factorization.

991724604605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172473 (or 172466 counting only the distinct ones).

The product of its (nonzero) digits is 3265920, while the sum is 53.

The spelling of 991724604605 in words is "nine hundred ninety-one billion, seven hundred twenty-four million, six hundred four thousand, six hundred five".