666605055550 has 48 divisors (see below), whose sum is σ = 1417124155392. Its totient is φ = 228532197600.

The previous prime is 666605055539. The next prime is 666605055551. The reversal of 666605055550 is 55550506666.

It is a junction number, because it is equal to n+sod(n) for n = 666605055494 and 666605055503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666605055551) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4797555 + ... + 4934545.

It is an arithmetic number, because the mean of its divisors is an integer number (29523419904).

Almost surely, 2^666605055550 is an apocalyptic number.

666605055550 is an abundant number, since it is smaller than the sum of its proper divisors (750519099842).

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

666605055550 is a wasteful number, since it uses less digits than its factorization.

666605055550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150913 (or 150908 counting only the distinct ones).

The product of its (nonzero) digits is 4050000, while the sum is 49.

The spelling of 666605055550 in words is "six hundred sixty-six billion, six hundred five million, fifty-five thousand, five hundred fifty".