991444077153 has 24 divisors (see below), whose sum is σ = 1476650762496. Its totient is φ = 640536660000.

The previous prime is 991444077119. The next prime is 991444077157. The reversal of 991444077153 is 351770444199.

991444077153 is a `hidden beast` number, since 99 + 144 + 407 + 7 + 1 + 5 + 3 = 666.

It is not a de Polignac number, because 991444077153 - 2⁸ = 991444076897 is a prime.

It is a super-2 number, since 2×991444077153² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 991444077153.

It is not an unprimeable number, because it can be changed into a prime (991444077157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5847313 + ... + 6014478.

It is an arithmetic number, because the mean of its divisors is an integer number (61527115104).

Almost surely, 2^991444077153 is an apocalyptic number.

It is an amenable number.

991444077153 is a deficient number, since it is larger than the sum of its proper divisors (485206685343).

991444077153 is a wasteful number, since it uses less digits than its factorization.

991444077153 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11862085 (or 11862082 counting only the distinct ones).

The product of its (nonzero) digits is 3810240, while the sum is 54.

The spelling of 991444077153 in words is "nine hundred ninety-one billion, four hundred forty-four million, seventy-seven thousand, one hundred fifty-three".