91880878 has 4 divisors (see below), whose sum is σ = 137821320. Its totient is φ = 45940438.

The previous prime is 91880863. The next prime is 91880909. The reversal of 91880878 is 87808819.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 22970218 + ... + 22970221.

It is an arithmetic number, because the mean of its divisors is an integer number (34455330).

Almost surely, 2^91880878 is an apocalyptic number.

91880878 is a deficient number, since it is larger than the sum of its proper divisors (45940442).

91880878 is a wasteful number, since it uses less digits than its factorization.

91880878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45940441.

The product of its (nonzero) digits is 258048, while the sum is 49.

The square root of 91880878 is about 9585.4513717404. The cubic root of 91880878 is about 451.2408190723.

It can be divided in two parts, 918 and 80878, that added together give a square (81796 = 286²).

The spelling of 91880878 in words is "ninety-one million, eight hundred eighty thousand, eight hundred seventy-eight".