180863561 has 4 divisors (see below), whose sum is σ = 191502612. Its totient is φ = 170224512.

The previous prime is 180863509. The next prime is 180863609. The reversal of 180863561 is 165368081.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 91087936 + 89775625 = 9544^2 + 9475^2 .

It is a cyclic number.

It is not a de Polignac number, because 180863561 - 2²² = 176669257 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (180866561) 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 3 ways as a sum of consecutive naturals, for example, 5319500 + ... + 5319533.

It is an arithmetic number, because the mean of its divisors is an integer number (47875653).

Almost surely, 2^180863561 is an apocalyptic number.

It is an amenable number.

180863561 is a deficient number, since it is larger than the sum of its proper divisors (10639051).

180863561 is a wasteful number, since it uses less digits than its factorization.

180863561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10639050.

The product of its (nonzero) digits is 34560, while the sum is 38.

The square root of 180863561 is about 13448.5523756276. The cubic root of 180863561 is about 565.5231127734.

The spelling of 180863561 in words is "one hundred eighty million, eight hundred sixty-three thousand, five hundred sixty-one".