181243636 has 12 divisors (see below), whose sum is σ = 362487328. Its totient is φ = 77675832.

The previous prime is 181243619. The next prime is 181243651. The reversal of 181243636 is 636342181.

It is a happy number.

181243636 is an admirable number.

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, 3236466 + ... + 3236521.

Almost surely, 2^181243636 is an apocalyptic number.

It is an amenable number.

181243636 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

181243636 is a wasteful number, since it uses less digits than its factorization.

181243636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6472998 (or 6472996 counting only the distinct ones).

The product of its digits is 20736, while the sum is 34.

The square root of 181243636 is about 13462.6756627351. The cubic root of 181243636 is about 565.9189743628.

The spelling of 181243636 in words is "one hundred eighty-one million, two hundred forty-three thousand, six hundred thirty-six".