665617044432 has 80 divisors (see below), whose sum is σ = 1742995584000. Its totient is φ = 218847587712.

The previous prime is 665617044403. The next prime is 665617044497. The reversal of 665617044432 is 234440716566.

It is a Harshad number since it is a multiple of its sum of digits (48).

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, 3777919 + ... + 3950177.

It is an arithmetic number, because the mean of its divisors is an integer number (21787444800).

Almost surely, 2^665617044432 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 665617044432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (871497792000).

665617044432 is an abundant number, since it is smaller than the sum of its proper divisors (1077378539568).

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

665617044432 is a wasteful number, since it uses less digits than its factorization.

665617044432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173368 (or 173362 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 48.

The spelling of 665617044432 in words is "six hundred sixty-five billion, six hundred seventeen million, forty-four thousand, four hundred thirty-two".