91166956397986 has 64 divisors (see below), whose sum is σ = 165672029894400. Its totient is φ = 36730453616640.

The previous prime is 91166956397981. The next prime is 91166956398019. The reversal of 91166956397986 is 68979365966119.

It is a happy number.

It is a super-2 number, since 2×91166956397986² (a number of 29 digits) contains 22 as substring.

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

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3814664665 + ... + 3814688563.

It is an arithmetic number, because the mean of its divisors is an integer number (2588625467100).

Almost surely, 2^{91166956397986} is an apocalyptic number.

91166956397986 is a deficient number, since it is larger than the sum of its proper divisors (74505073496414).

91166956397986 is a wasteful number, since it uses less digits than its factorization.

91166956397986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41899.

The product of its digits is 7142567040, while the sum is 85.

The spelling of 91166956397986 in words is "ninety-one trillion, one hundred sixty-six billion, nine hundred fifty-six million, three hundred ninety-seven thousand, nine hundred eighty-six".