117777891 has 24 divisors (see below), whose sum is σ = 197274112. Its totient is φ = 61182000.

The previous prime is 117777889. The next prime is 117777899. The reversal of 117777891 is 198777711.

It is not a de Polignac number, because 117777891 - 2¹ = 117777889 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 117777891.

It is not an unprimeable number, because it can be changed into a prime (117777899) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20635 + ... + 25716.

Almost surely, 2^117777891 is an apocalyptic number.

117777891 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

117777891 is a deficient number, since it is larger than the sum of its proper divisors (79496221).

117777891 is a wasteful number, since it uses less digits than its factorization.

117777891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46383 (or 46372 counting only the distinct ones).

The product of its digits is 172872, while the sum is 48.

The square root of 117777891 is about 10852.5522804546. The cubic root of 117777891 is about 490.1788754124.

The spelling of 117777891 in words is "one hundred seventeen million, seven hundred seventy-seven thousand, eight hundred ninety-one".