516945182121 has 27 divisors (see below), whose sum is σ = 749773850007. Its totient is φ = 343216589040.

The previous prime is 516945182119. The next prime is 516945182129. The reversal of 516945182121 is 121281549615.

The square root of 516945182121 is 718989.

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

516945182121 is a `hidden beast` number, since 5 + 1 + 6 + 9 + 4 + 518 + 2 + 121 = 666.

It can be written as a sum of positive squares in only one way, i.e., 205380269721 + 311564912400 = 453189^2 + 558180^2 .

It is not a de Polignac number, because 516945182121 - 2¹ = 516945182119 is a prime.

It is a super-3 number, since 3×516945182121³ (a number of 36 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (516945182129) 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, 955536111 + ... + 955536651.

Almost surely, 2^516945182121 is an apocalyptic number.

516945182121 is the 718989-th square number.

516945182121 is the 359495-th centered octagonal number.

It is an amenable number.

516945182121 is a deficient number, since it is larger than the sum of its proper divisors (232828667886).

516945182121 is an frugal number, since it uses more digits than its factorization.

516945182121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1974 (or 987 counting only the distinct ones).

The product of its digits is 172800, while the sum is 45.

The spelling of 516945182121 in words is "five hundred sixteen billion, nine hundred forty-five million, one hundred eighty-two thousand, one hundred twenty-one".