661363506 has 24 divisors (see below), whose sum is σ = 1433659500. Its totient is φ = 220346016.

The previous prime is 661363489. The next prime is 661363519. The reversal of 661363506 is 605363166.

It is a happy number.

661363506 is a `hidden beast` number, since 6 + 6 + 13 + 635 + 0 + 6 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 561263481 + 100100025 = 23691^2 + 10005^2 .

It is a super-2 number, since 2×661363506² = 874803374137224072, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34120 + ... + 49868.

Almost surely, 2^661363506 is an apocalyptic number.

661363506 is an abundant number, since it is smaller than the sum of its proper divisors (772295994).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

661363506 is a wasteful number, since it uses less digits than its factorization.

661363506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18090 (or 18087 counting only the distinct ones).

The product of its (nonzero) digits is 58320, while the sum is 36.

The square root of 661363506 is about 25716.9886650829. The cubic root of 661363506 is about 871.2579266302.

The spelling of 661363506 in words is "six hundred sixty-one million, three hundred sixty-three thousand, five hundred six".