505940661 has 10 divisors (see below), whose sum is σ = 755788022. Its totient is φ = 337293720.

The previous prime is 505940657. The next prime is 505940681. The reversal of 505940661 is 166049505.

505940661 is a `hidden beast` number, since 5 + 0 + 594 + 0 + 6 + 61 = 666.

It can be written as a sum of positive squares in only one way, i.e., 430355025 + 75585636 = 20745^2 + 8694^2 .

It is not a de Polignac number, because 505940661 - 2² = 505940657 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 (505940681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 3123010 + ... + 3123171.

Almost surely, 2^505940661 is an apocalyptic number.

It is an amenable number.

505940661 is a deficient number, since it is larger than the sum of its proper divisors (249847361).

505940661 is an equidigital number, since it uses as much as digits as its factorization.

505940661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6246193 (or 6246184 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 505940661 is about 22493.1247495763. The cubic root of 505940661 is about 796.8315620890.

The spelling of 505940661 in words is "five hundred five million, nine hundred forty thousand, six hundred sixty-one".