506611661 has 4 divisors (see below), whose sum is σ = 509719872. Its totient is φ = 503503452.

The previous prime is 506611631. The next prime is 506611663. The reversal of 506611661 is 166116605.

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 a cyclic number.

It is not a de Polignac number, because 506611661 - 2⁶ = 506611597 is a prime.

It is a super-2 number, since 2×506611661² = 513310750122357842, 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 (506611663) 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, 1553861 + ... + 1554186.

It is an arithmetic number, because the mean of its divisors is an integer number (127429968).

Almost surely, 2^506611661 is an apocalyptic number.

It is an amenable number.

506611661 is a deficient number, since it is larger than the sum of its proper divisors (3108211).

506611661 is a wasteful number, since it uses less digits than its factorization.

506611661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3108210.

The product of its (nonzero) digits is 6480, while the sum is 32.

The square root of 506611661 is about 22508.0354762471. The cubic root of 506611661 is about 797.1836704317.

The spelling of 506611661 in words is "five hundred six million, six hundred eleven thousand, six hundred sixty-one".