116121591 has 6 divisors (see below), whose sum is σ = 167731200. Its totient is φ = 77414388.

The previous prime is 116121589. The next prime is 116121659. The reversal of 116121591 is 195121611.

116121591 is a `hidden beast` number, since 11 + 61 + 2 + 1 + 591 = 666.

It is not a de Polignac number, because 116121591 - 2¹ = 116121589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (116121581) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6451191 + ... + 6451208.

It is an arithmetic number, because the mean of its divisors is an integer number (27955200).

Almost surely, 2^116121591 is an apocalyptic number.

116121591 is a deficient number, since it is larger than the sum of its proper divisors (51609609).

116121591 is a wasteful number, since it uses less digits than its factorization.

116121591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12902405 (or 12902402 counting only the distinct ones).

The product of its digits is 540, while the sum is 27.

The square root of 116121591 is about 10775.9728563133. The cubic root of 116121591 is about 487.8702386670.

It can be divided in two parts, 11612 and 1591, that added together give a triangular number (13203 = T₁₆₂).

The spelling of 116121591 in words is "one hundred sixteen million, one hundred twenty-one thousand, five hundred ninety-one".