136818891 has 24 divisors (see below), whose sum is σ = 218821824. Its totient is φ = 81678960.

The previous prime is 136818883. The next prime is 136818893. The reversal of 136818891 is 198818631.

136818891 = T₃₁₇₀ + T₃₁₇₁ + ... + T₃₁₉₆.

It is not a de Polignac number, because 136818891 - 2³ = 136818883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (136818893) 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, 3681 + ... + 16946.

It is an arithmetic number, because the mean of its divisors is an integer number (9117576).

Almost surely, 2^136818891 is an apocalyptic number.

136818891 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

136818891 is a deficient number, since it is larger than the sum of its proper divisors (82002933).

136818891 is a wasteful number, since it uses less digits than its factorization.

136818891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20711 (or 20708 counting only the distinct ones).

The product of its digits is 82944, while the sum is 45.

The square root of 136818891 is about 11696.9607591032. The cubic root of 136818891 is about 515.2864099527.

The spelling of 136818891 in words is "one hundred thirty-six million, eight hundred eighteen thousand, eight hundred ninety-one".