518021380 has 24 divisors (see below), whose sum is σ = 1097476632. Its totient is φ = 205373952.

The previous prime is 518021353. The next prime is 518021401. The reversal of 518021380 is 83120815.

It can be written as a sum of positive squares in 4 ways, for example, as 54997056 + 463024324 = 7416^2 + 21518^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 112347 + ... + 116866.

It is an arithmetic number, because the mean of its divisors is an integer number (45728193).

Almost surely, 2^518021380 is an apocalyptic number.

It is an amenable number.

518021380 is an abundant number, since it is smaller than the sum of its proper divisors (579455252).

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

518021380 is a wasteful number, since it uses less digits than its factorization.

518021380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229335 (or 229333 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 518021380 is about 22760.0830402703. The cubic root of 518021380 is about 803.1239209360.

The spelling of 518021380 in words is "five hundred eighteen million, twenty-one thousand, three hundred eighty".