91638165715 has 8 divisors (see below), whose sum is σ = 110014191648. Its totient is φ = 73278270720.

The previous prime is 91638165713. The next prime is 91638165743. The reversal of 91638165715 is 51756183619.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 91638165715 - 2¹ = 91638165713 is a prime.

It is a super-2 number, since 2×91638165715² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91638165713) 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 7 ways as a sum of consecutive naturals, for example, 4020231 + ... + 4042960.

It is an arithmetic number, because the mean of its divisors is an integer number (13751773956).

Almost surely, 2^91638165715 is an apocalyptic number.

91638165715 is a deficient number, since it is larger than the sum of its proper divisors (18376025933).

91638165715 is a wasteful number, since it uses less digits than its factorization.

91638165715 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8065469.

The product of its digits is 1360800, while the sum is 52.

The spelling of 91638165715 in words is "ninety-one billion, six hundred thirty-eight million, one hundred sixty-five thousand, seven hundred fifteen".