91113978 has 8 divisors (see below), whose sum is σ = 182227968. Its totient is φ = 30371324.

The previous prime is 91113977. The next prime is 91114003. The reversal of 91113978 is 87931119.

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

91113978 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (91113973) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7592826 + ... + 7592837.

It is an arithmetic number, because the mean of its divisors is an integer number (22778496).

Almost surely, 2^91113978 is an apocalyptic number.

91113978 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91113978 is a wasteful number, since it uses less digits than its factorization.

91113978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15185668.

The product of its digits is 13608, while the sum is 39.

The square root of 91113978 is about 9545.3642151570. The cubic root of 91113978 is about 449.9818560586.

The spelling of 91113978 in words is "ninety-one million, one hundred thirteen thousand, nine hundred seventy-eight".