661110066 has 16 divisors (see below), whose sum is σ = 1469133600. Its totient is φ = 220370004.

The previous prime is 661110031. The next prime is 661110143. The reversal of 661110066 is 660011166.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a zygodrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6121336 + ... + 6121443.

It is an arithmetic number, because the mean of its divisors is an integer number (91820850).

Almost surely, 2^661110066 is an apocalyptic number.

661110066 is an abundant number, since it is smaller than the sum of its proper divisors (808023534).

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

661110066 is a wasteful number, since it uses less digits than its factorization.

661110066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12242790 (or 12242784 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 661110066 is about 25712.0607108804. The cubic root of 661110066 is about 871.1466213150.

It can be divided in two parts, 6611100 and 66, that added together give a palindrome (6611166).

The spelling of 661110066 in words is "six hundred sixty-one million, one hundred ten thousand, sixty-six".