521116509456 has 135 divisors (see below), whose sum is σ = 1494175572279. Its totient is φ = 169544563776.

The previous prime is 521116509421. The next prime is 521116509469. The reversal of 521116509456 is 654905611125.

The square root of 521116509456 is 721884.

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

521116509456 is a `hidden beast` number, since 5 + 21 + 116 + 509 + 4 + 5 + 6 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 372491445 + ... + 372492843.

Almost surely, 2^521116509456 is an apocalyptic number.

521116509456 is the 721884-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 521116509456

521116509456 is an abundant number, since it is smaller than the sum of its proper divisors (973059062823).

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

521116509456 is an equidigital number, since it uses as much as digits as its factorization.

521116509456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2898 (or 1447 counting only the distinct ones).

The product of its (nonzero) digits is 324000, while the sum is 45.

The spelling of 521116509456 in words is "five hundred twenty-one billion, one hundred sixteen million, five hundred nine thousand, four hundred fifty-six".