660423444 has 12 divisors (see below), whose sum is σ = 1540988064. Its totient is φ = 220141144.

The previous prime is 660423389. The next prime is 660423457. The reversal of 660423444 is 444324066.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-3 number, since 3×660423444³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent 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, 27517632 + ... + 27517655.

It is an arithmetic number, because the mean of its divisors is an integer number (128415672).

Almost surely, 2^660423444 is an apocalyptic number.

It is an amenable number.

660423444 is an abundant number, since it is smaller than the sum of its proper divisors (880564620).

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

660423444 is a wasteful number, since it uses less digits than its factorization.

660423444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55035294 (or 55035292 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 33.

The square root of 660423444 is about 25698.7051035650. The cubic root of 660423444 is about 870.8449289228.

The spelling of 660423444 in words is "six hundred sixty million, four hundred twenty-three thousand, four hundred forty-four".