15664666 has 8 divisors (see below), whose sum is σ = 23518944. Its totient is φ = 7825020.

The previous prime is 15664657. The next prime is 15664681. The reversal of 15664666 is 66646651.

15664666 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 400 + ... + 5611.

It is an arithmetic number, because the mean of its divisors is an integer number (2939868).

Almost surely, 2^15664666 is an apocalyptic number.

15664666 is a deficient number, since it is larger than the sum of its proper divisors (7854278).

15664666 is a wasteful number, since it uses less digits than its factorization.

15664666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7316.

The product of its digits is 155520, while the sum is 40.

The square root of 15664666 is about 3957.8612911521. The cubic root of 15664666 is about 250.2113732351.

The spelling of 15664666 in words is "fifteen million, six hundred sixty-four thousand, six hundred sixty-six".