180394821 has 6 divisors (see below), whose sum is σ = 260570310. Its totient is φ = 120263208.

The previous prime is 180394811. The next prime is 180394843. The reversal of 180394821 is 128493081.

It can be written as a sum of positive squares in only one way, i.e., 126900225 + 53494596 = 11265^2 + 7314^2 .

It is not a de Polignac number, because 180394821 - 2⁶ = 180394757 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (180394811) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10021926 + ... + 10021943.

It is an arithmetic number, because the mean of its divisors is an integer number (43428385).

Almost surely, 2^180394821 is an apocalyptic number.

It is an amenable number.

180394821 is a deficient number, since it is larger than the sum of its proper divisors (80175489).

180394821 is a wasteful number, since it uses less digits than its factorization.

180394821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20043875 (or 20043872 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 180394821 is about 13431.1139150854. The cubic root of 180394821 is about 565.0341389558.

The spelling of 180394821 in words is "one hundred eighty million, three hundred ninety-four thousand, eight hundred twenty-one".