516873285721 has 27 divisors (see below), whose sum is σ = 579960515901. Its totient is φ = 460420038624.

The previous prime is 516873285683. The next prime is 516873285767. The reversal of 516873285721 is 127582378615.

It is a happy number.

The square root of 516873285721 is 718939.

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

It can be written as a sum of positive squares in 4 ways, for example, as 66277928025 + 450595357696 = 257445^2 + 671264^2 .

It is not a de Polignac number, because 516873285721 - 2⁹ = 516873285209 is a prime.

It is not an unprimeable number, because it can be changed into a prime (516873285781) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 271039050 + ... + 271040956.

Almost surely, 2^516873285721 is an apocalyptic number.

516873285721 is the 718939-th square number.

516873285721 is the 359470-th centered octagonal number.

It is an amenable number.

516873285721 is a deficient number, since it is larger than the sum of its proper divisors (63087230180).

516873285721 is an frugal number, since it uses more digits than its factorization.

516873285721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3898 (or 1949 counting only the distinct ones).

The product of its digits is 5644800, while the sum is 55.

The spelling of 516873285721 in words is "five hundred sixteen billion, eight hundred seventy-three million, two hundred eighty-five thousand, seven hundred twenty-one".