181604772 has 18 divisors (see below), whose sum is σ = 459056598. Its totient is φ = 60534912.

The previous prime is 181604743. The next prime is 181604783. The reversal of 181604772 is 277406181.

181604772 is a `hidden beast` number, since 181 + 6 + 0 + 477 + 2 = 666.

181604772 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., 143856036 + 37748736 = 11994^2 + 6144^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 5044577 = 181604772 / (1 + 8 + 1 + 6 + 0 + 4 + 7 + 7 + 2).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2522253 + ... + 2522324.

Almost surely, 2^181604772 is an apocalyptic number.

181604772 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

181604772 is an abundant number, since it is smaller than the sum of its proper divisors (277451826).

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

181604772 is a wasteful number, since it uses less digits than its factorization.

181604772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5044587 (or 5044582 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 36.

The square root of 181604772 is about 13476.0814779371. The cubic root of 181604772 is about 566.2945978937.

The spelling of 181604772 in words is "one hundred eighty-one million, six hundred four thousand, seven hundred seventy-two".