1666604606 has 4 divisors (see below), whose sum is σ = 2499906912. Its totient is φ = 833302302.

The previous prime is 1666604593. The next prime is 1666604677. The reversal of 1666604606 is 6064066661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6064066661 = 5011 ⋅1210151.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 416651150 + ... + 416651153.

It is an arithmetic number, because the mean of its divisors is an integer number (624976728).

Almost surely, 2^1666604606 is an apocalyptic number.

1666604606 is a deficient number, since it is larger than the sum of its proper divisors (833302306).

1666604606 is an equidigital number, since it uses as much as digits as its factorization.

1666604606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 833302305.

The product of its (nonzero) digits is 186624, while the sum is 41.

The square root of 1666604606 is about 40824.0689544783. The cubic root of 1666604606 is about 1185.6163851027.

The spelling of 1666604606 in words is "one billion, six hundred sixty-six million, six hundred four thousand, six hundred six".