668532444 has 48 divisors (see below), whose sum is σ = 1648389120. Its totient is φ = 210450240.

The previous prime is 668532413. The next prime is 668532451. The reversal of 668532444 is 444235866.

It is a super-2 number, since 2×668532444² = 893871257361226272, which contains 22 as substring.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 668532396 and 668532405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6474 + ... + 37134.

It is an arithmetic number, because the mean of its divisors is an integer number (34341440).

Almost surely, 2^668532444 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 668532444, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (824194560).

668532444 is an abundant number, since it is smaller than the sum of its proper divisors (979856676).

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

668532444 is a wasteful number, since it uses less digits than its factorization.

668532444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30770 (or 30768 counting only the distinct ones).

The product of its digits is 552960, while the sum is 42.

The square root of 668532444 is about 25855.9943533410. The cubic root of 668532444 is about 874.3946589704.

The spelling of 668532444 in words is "six hundred sixty-eight million, five hundred thirty-two thousand, four hundred forty-four".