515540420 has 12 divisors (see below), whose sum is σ = 1082634924. Its totient is φ = 206216160.

The previous prime is 515540401. The next prime is 515540477. The reversal of 515540420 is 24045515.

It can be written as a sum of positive squares in 2 ways, for example, as 243422404 + 272118016 = 15602^2 + 16496^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 515540420.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12888491 + ... + 12888530.

It is an arithmetic number, because the mean of its divisors is an integer number (90219577).

Almost surely, 2^515540420 is an apocalyptic number.

It is an amenable number.

515540420 is an abundant number, since it is smaller than the sum of its proper divisors (567094504).

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

515540420 is a wasteful number, since it uses less digits than its factorization.

515540420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25777030 (or 25777028 counting only the distinct ones).

The product of its (nonzero) digits is 4000, while the sum is 26.

The square root of 515540420 is about 22705.5151890460. The cubic root of 515540420 is about 801.8397347270.

Adding to 515540420 its reverse (24045515), we get a palindrome (539585935).

The spelling of 515540420 in words is "five hundred fifteen million, five hundred forty thousand, four hundred twenty".