91856972151 has 48 divisors (see below), whose sum is σ = 162756270144. Its totient is φ = 48725286912.

The previous prime is 91856972047. The next prime is 91856972201. The reversal of 91856972151 is 15127965819.

It is a happy number.

91856972151 is a `hidden beast` number, since 9 + 1 + 8 + 569 + 7 + 21 + 51 = 666.

It is not a de Polignac number, because 91856972151 - 2¹⁷ = 91856841079 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91856972551) 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 47 ways as a sum of consecutive naturals, for example, 509266 + ... + 665631.

It is an arithmetic number, because the mean of its divisors is an integer number (3390755628).

Almost surely, 2^91856972151 is an apocalyptic number.

91856972151 is a deficient number, since it is larger than the sum of its proper divisors (70899297993).

91856972151 is a wasteful number, since it uses less digits than its factorization.

91856972151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1175000 (or 1174997 counting only the distinct ones).

The product of its digits is 1360800, while the sum is 54.

The spelling of 91856972151 in words is "ninety-one billion, eight hundred fifty-six million, nine hundred seventy-two thousand, one hundred fifty-one".