516581645 has 4 divisors (see below), whose sum is σ = 619897980. Its totient is φ = 413265312.

The previous prime is 516581641. The next prime is 516581651. The reversal of 516581645 is 546185615.

516581645 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 244265641 + 272316004 = 15629^2 + 16502^2 .

It is a cyclic number.

It is not a de Polignac number, because 516581645 - 2² = 516581641 is a prime.

It is a super-3 number, since 3×516581645³ (a number of 27 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (516581641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51658160 + ... + 51658169.

It is an arithmetic number, because the mean of its divisors is an integer number (154974495).

Almost surely, 2^516581645 is an apocalyptic number.

It is an amenable number.

516581645 is a deficient number, since it is larger than the sum of its proper divisors (103316335).

516581645 is a wasteful number, since it uses less digits than its factorization.

516581645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103316334.

The product of its digits is 144000, while the sum is 41.

The square root of 516581645 is about 22728.4325240435. The cubic root of 516581645 is about 802.3791907375.

The spelling of 516581645 in words is "five hundred sixteen million, five hundred eighty-one thousand, six hundred forty-five".