555555661506 has 12 divisors (see below), whose sum is σ = 1203703933302. Its totient is φ = 185185220496.

The previous prime is 555555661487. The next prime is 555555661519. The reversal of 555555661506 is 605166555555.

It can be written as a sum of positive squares in only one way, i.e., 533836270881 + 21719390625 = 730641^2 + 147375^2 .

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 5 ways as a sum of consecutive naturals, for example, 15432101691 + ... + 15432101726.

Almost surely, 2^555555661506 is an apocalyptic number.

555555661506 is an abundant number, since it is smaller than the sum of its proper divisors (648148271796).

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

555555661506 is a wasteful number, since it uses less digits than its factorization.

555555661506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30864203425 (or 30864203422 counting only the distinct ones).

The product of its (nonzero) digits is 16875000, while the sum is 54.

The spelling of 555555661506 in words is "five hundred fifty-five billion, five hundred fifty-five million, six hundred sixty-one thousand, five hundred six".