91166956397987 has 8 divisors (see below), whose sum is σ = 92717652462336. Its totient is φ = 89621848428552.

The previous prime is 91166956397981. The next prime is 91166956398019. The reversal of 91166956397987 is 78979365966119.

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

It is a cyclic number.

It is not a de Polignac number, because 91166956397987 - 2¹⁴ = 91166956381603 is a prime.

It is a super-2 number, since 2×91166956397987² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 91166956397899 and 91166956397908.

It is not an unprimeable number, because it can be changed into a prime (91166956397981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1396990823 + ... + 1397056080.

It is an arithmetic number, because the mean of its divisors is an integer number (11589706557792).

Almost surely, 2^{91166956397987} is an apocalyptic number.

91166956397987 is a deficient number, since it is larger than the sum of its proper divisors (1550696064349).

91166956397987 is a wasteful number, since it uses less digits than its factorization.

91166956397987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2794047457.

The product of its digits is 8332994880, while the sum is 86.

The spelling of 91166956397987 in words is "ninety-one trillion, one hundred sixty-six billion, nine hundred fifty-six million, three hundred ninety-seven thousand, nine hundred eighty-seven".