181368636 has 12 divisors (see below), whose sum is σ = 423193512. Its totient is φ = 60456208.

The previous prime is 181368619. The next prime is 181368643. The reversal of 181368636 is 636863181.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7557015 + ... + 7557038.

It is an arithmetic number, because the mean of its divisors is an integer number (35266126).

Almost surely, 2^181368636 is an apocalyptic number.

It is an amenable number.

181368636 is an abundant number, since it is smaller than the sum of its proper divisors (241824876).

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

181368636 is a wasteful number, since it uses less digits than its factorization.

181368636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15114060 (or 15114058 counting only the distinct ones).

The product of its digits is 124416, while the sum is 42.

The square root of 181368636 is about 13467.3173275155. The cubic root of 181368636 is about 566.0490453490.

The spelling of 181368636 in words is "one hundred eighty-one million, three hundred sixty-eight thousand, six hundred thirty-six".