91861115 has 32 divisors (see below), whose sum is σ = 122544576. Its totient is φ = 65802240.

The previous prime is 91861093. The next prime is 91861117. The reversal of 91861115 is 51116819.

It is not a de Polignac number, because 91861115 - 2⁶ = 91861051 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91861117) 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, 149549 + ... + 150161.

It is an arithmetic number, because the mean of its divisors is an integer number (3829518).

Almost surely, 2^91861115 is an apocalyptic number.

91861115 is a deficient number, since it is larger than the sum of its proper divisors (30683461).

91861115 is a wasteful number, since it uses less digits than its factorization.

91861115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 719.

The product of its digits is 2160, while the sum is 32.

The square root of 91861115 is about 9584.4204310955. The cubic root of 91861115 is about 451.2084637300.

It can be divided in two parts, 9186 and 1115, that added together give a palindrome (10301).

The spelling of 91861115 in words is "ninety-one million, eight hundred sixty-one thousand, one hundred fifteen".