1660655666 has 8 divisors (see below), whose sum is σ = 2502789744. Its totient is φ = 826392420.

The previous prime is 1660655639. The next prime is 1660655669. The reversal of 1660655666 is 6665560661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 1660655666.

It is not an unprimeable number, because it can be changed into a prime (1660655669) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1967180 + ... + 1968023.

It is an arithmetic number, because the mean of its divisors is an integer number (312848718).

Almost surely, 2^1660655666 is an apocalyptic number.

1660655666 is a deficient number, since it is larger than the sum of its proper divisors (842134078).

1660655666 is a wasteful number, since it uses less digits than its factorization.

1660655666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3935416.

The product of its (nonzero) digits is 1166400, while the sum is 47.

The square root of 1660655666 is about 40751.1431250707. The cubic root of 1660655666 is about 1184.2040186116.

The spelling of 1660655666 in words is "one billion, six hundred sixty million, six hundred fifty-five thousand, six hundred sixty-six".