513660621 has 4 divisors (see below), whose sum is σ = 684880832. Its totient is φ = 342440412.

The previous prime is 513660617. The next prime is 513660629. The reversal of 513660621 is 126066315.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 513660621 - 2² = 513660617 is a prime.

It is a super-2 number, since 2×513660621² = 527694467132211282, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (513660629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 85610101 + ... + 85610106.

It is an arithmetic number, because the mean of its divisors is an integer number (171220208).

Almost surely, 2^513660621 is an apocalyptic number.

It is an amenable number.

513660621 is a deficient number, since it is larger than the sum of its proper divisors (171220211).

513660621 is a wasteful number, since it uses less digits than its factorization.

513660621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171220210.

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 513660621 is about 22664.0821786368. The cubic root of 513660621 is about 800.8639733725.

The spelling of 513660621 in words is "five hundred thirteen million, six hundred sixty thousand, six hundred twenty-one".