180606721 has 9 divisors (see below), whose sum is σ = 183876483. Its totient is φ = 177394800.

The previous prime is 180606709. The next prime is 180606733. The reversal of 180606721 is 127606081.

The square root of 180606721 is 13439.

It is a perfect power (a square), and thus also a powerful number.

It is an interprime number because it is at equal distance from previous prime (180606709) and next prime (180606733).

It can be written as a sum of positive squares in only one way, i.e., 34680321 + 145926400 = 5889^2 + 12080^2 .

It is a de Polignac number, because none of the positive numbers 2^k-180606721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (180646721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1195996 + ... + 1196146.

Almost surely, 2^180606721 is an apocalyptic number.

180606721 is the 13439-th square number.

180606721 is the 6720-th centered octagonal number.

It is an amenable number.

180606721 is a deficient number, since it is larger than the sum of its proper divisors (3269762).

180606721 is an frugal number, since it uses more digits than its factorization.

180606721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 480 (or 240 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 31.

The cubic root of 180606721 is about 565.2552906931.

The spelling of 180606721 in words is "one hundred eighty million, six hundred six thousand, seven hundred twenty-one".