91859859 has 80 divisors (see below), whose sum is σ = 172541600. Its totient is φ = 48009024.

The previous prime is 91859827. The next prime is 91859893. The reversal of 91859859 is 95895819.

It is not a de Polignac number, because 91859859 - 2⁵ = 91859827 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91859809) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 842697 + ... + 842805.

It is an arithmetic number, because the mean of its divisors is an integer number (2156770).

Almost surely, 2^91859859 is an apocalyptic number.

91859859 is a deficient number, since it is larger than the sum of its proper divisors (80681741).

91859859 is a wasteful number, since it uses less digits than its factorization.

91859859 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159 (or 132 counting only the distinct ones).

The product of its digits is 1166400, while the sum is 54.

The square root of 91859859 is about 9584.3549078694. The cubic root of 91859859 is about 451.2064072907.

It can be divided in two parts, 9185 and 9859, that added together give a square (19044 = 138²).

The spelling of 91859859 in words is "ninety-one million, eight hundred fifty-nine thousand, eight hundred fifty-nine".