520207661 has 8 divisors (see below), whose sum is σ = 529864800. Its totient is φ = 510578640.

The previous prime is 520207657. The next prime is 520207733. The reversal of 520207661 is 166702025.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 520207661 - 2² = 520207657 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (520207651) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32330 + ... + 45668.

It is an arithmetic number, because the mean of its divisors is an integer number (66233100).

Almost surely, 2^520207661 is an apocalyptic number.

It is an amenable number.

520207661 is a deficient number, since it is larger than the sum of its proper divisors (9657139).

520207661 is a wasteful number, since it uses less digits than its factorization.

520207661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14059.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 520207661 is about 22808.0613161224. The cubic root of 520207661 is about 804.2521820783.

Adding to 520207661 its reverse (166702025), we get a palindrome (686909686).

The spelling of 520207661 in words is "five hundred twenty million, two hundred seven thousand, six hundred sixty-one".