665222646 has 16 divisors (see below), whose sum is σ = 1451395008. Its totient is φ = 201582600.

The previous prime is 665222567. The next prime is 665222671. The reversal of 665222646 is 646222566.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5039500 + ... + 5039631.

It is an arithmetic number, because the mean of its divisors is an integer number (90712188).

Almost surely, 2^665222646 is an apocalyptic number.

665222646 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

665222646 is an abundant number, since it is smaller than the sum of its proper divisors (786172362).

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

665222646 is a wasteful number, since it uses less digits than its factorization.

665222646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10079147.

The product of its digits is 207360, while the sum is 39.

The square root of 665222646 is about 25791.9104759613. The cubic root of 665222646 is about 872.9492746684.

The spelling of 665222646 in words is "six hundred sixty-five million, two hundred twenty-two thousand, six hundred forty-six".