91421757567 has 16 divisors (see below), whose sum is σ = 154788161280. Its totient is φ = 52241004216.

The previous prime is 91421757521. The next prime is 91421757577. The reversal of 91421757567 is 76575712419.

91421757567 is a `hidden beast` number, since 9 + 1 + 4 + 2 + 1 + 7 + 575 + 67 = 666.

It is not a de Polignac number, because 91421757567 - 2¹¹ = 91421755519 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91421757577) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 241856313 + ... + 241856690.

It is an arithmetic number, because the mean of its divisors is an integer number (9674260080).

Almost surely, 2^91421757567 is an apocalyptic number.

91421757567 is a deficient number, since it is larger than the sum of its proper divisors (63366403713).

91421757567 is a wasteful number, since it uses less digits than its factorization.

91421757567 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 483713019 (or 483713013 counting only the distinct ones).

The product of its digits is 3704400, while the sum is 54.

The spelling of 91421757567 in words is "ninety-one billion, four hundred twenty-one million, seven hundred fifty-seven thousand, five hundred sixty-seven".