309990666 has 8 divisors (see below), whose sum is σ = 619981344. Its totient is φ = 103330220.

The previous prime is 309990581. The next prime is 309990673. The reversal of 309990666 is 666099903.

309990666 is digitally balanced in base 3, 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.

309990666 is an admirable number.

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, 25832550 + ... + 25832561.

It is an arithmetic number, because the mean of its divisors is an integer number (77497668).

Almost surely, 2^309990666 is an apocalyptic number.

309990666 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

309990666 is a wasteful number, since it uses less digits than its factorization.

309990666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51665116.

The product of its (nonzero) digits is 472392, while the sum is 48.

The square root of 309990666 is about 17606.5517918757. The cubic root of 309990666 is about 676.7831525002.

The spelling of 309990666 in words is "three hundred nine million, nine hundred ninety thousand, six hundred sixty-six".