331656666 has 64 divisors (see below), whose sum is σ = 772346880. Its totient is φ = 93882240.

The previous prime is 331656659. The next prime is 331656671. The reversal of 331656666 is 666656133.

It is a super-2 number, since 2×331656666² = 219992288204471112, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 89731 + ... + 93353.

It is an arithmetic number, because the mean of its divisors is an integer number (12067920).

Almost surely, 2^331656666 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 331656666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (386173440).

331656666 is an abundant number, since it is smaller than the sum of its proper divisors (440690214).

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

331656666 is a wasteful number, since it uses less digits than its factorization.

331656666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3731.

The product of its digits is 349920, while the sum is 42.

The square root of 331656666 is about 18211.4432706472. The cubic root of 331656666 is about 692.1967835000.

The spelling of 331656666 in words is "three hundred thirty-one million, six hundred fifty-six thousand, six hundred sixty-six".