118778891 has 12 divisors (see below), whose sum is σ = 150733080. Its totient is φ = 92554560.

The previous prime is 118778797. The next prime is 118778941. The reversal of 118778891 is 198877811.

It is not a de Polignac number, because 118778891 - 2²⁶ = 51670027 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (118778591) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 109646 + ... + 110723.

It is an arithmetic number, because the mean of its divisors is an integer number (12561090).

Almost surely, 2^118778891 is an apocalyptic number.

118778891 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

118778891 is a deficient number, since it is larger than the sum of its proper divisors (31954189).

118778891 is a wasteful number, since it uses less digits than its factorization.

118778891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220394 (or 220387 counting only the distinct ones).

The product of its digits is 225792, while the sum is 50.

The square root of 118778891 is about 10898.5728882272. The cubic root of 118778891 is about 491.5636443854.

The spelling of 118778891 in words is "one hundred eighteen million, seven hundred seventy-eight thousand, eight hundred ninety-one".