991013634613 has 4 divisors (see below), whose sum is σ = 1034101183968. Its totient is φ = 947926085260.

The previous prime is 991013634581. The next prime is 991013634617. The reversal of 991013634613 is 316436310199.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 991013634613 - 2⁵ = 991013634581 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991013634617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21543774643 + ... + 21543774688.

It is an arithmetic number, because the mean of its divisors is an integer number (258525295992).

Almost surely, 2^991013634613 is an apocalyptic number.

It is an amenable number.

991013634613 is a deficient number, since it is larger than the sum of its proper divisors (43087549355).

991013634613 is a wasteful number, since it uses less digits than its factorization.

991013634613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43087549354.

The product of its (nonzero) digits is 314928, while the sum is 46.

The spelling of 991013634613 in words is "nine hundred ninety-one billion, thirteen million, six hundred thirty-four thousand, six hundred thirteen".