181406538 has 12 divisors (see below), whose sum is σ = 393047538. Its totient is φ = 60468840.

The previous prime is 181406531. The next prime is 181406539. The reversal of 181406538 is 835604181.

181406538 is a `hidden beast` number, since 1 + 81 + 40 + 6 + 538 = 666.

181406538 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 100460529 + 80946009 = 10023^2 + 8997^2 .

It is not an unprimeable number, because it can be changed into a prime (181406531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5039053 + ... + 5039088.

Almost surely, 2^181406538 is an apocalyptic number.

181406538 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

181406538 is an abundant number, since it is smaller than the sum of its proper divisors (211641000).

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

181406538 is a wasteful number, since it uses less digits than its factorization.

181406538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10078149 (or 10078146 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 181406538 is about 13468.7244384908. The cubic root of 181406538 is about 566.0884731447.

The spelling of 181406538 in words is "one hundred eighty-one million, four hundred six thousand, five hundred thirty-eight".