515994981 has 24 divisors (see below), whose sum is σ = 706733664. Its totient is φ = 334815840.

The previous prime is 515994979. The next prime is 515995001. The reversal of 515994981 is 189499515.

It is not a de Polignac number, because 515994981 - 2¹ = 515994979 is a prime.

It is a super-2 number, since 2×515994981² = 532501640834380722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (515994901) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2850711 + ... + 2850891.

It is an arithmetic number, because the mean of its divisors is an integer number (29447236).

Almost surely, 2^515994981 is an apocalyptic number.

It is an amenable number.

515994981 is a deficient number, since it is larger than the sum of its proper divisors (190738683).

515994981 is a wasteful number, since it uses less digits than its factorization.

515994981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 481 (or 374 counting only the distinct ones).

The product of its digits is 583200, while the sum is 51.

The square root of 515994981 is about 22715.5229083550. The cubic root of 515994981 is about 802.0753308676.

The spelling of 515994981 in words is "five hundred fifteen million, nine hundred ninety-four thousand, nine hundred eighty-one".