665636415232 has 72 divisors (see below), whose sum is σ = 1356090982400. Its totient is φ = 326016617472.

The previous prime is 665636415221. The next prime is 665636415247. The reversal of 665636415232 is 232514636566.

It is a super-2 number, since 2×665636415232² (a number of 24 digits) contains 22 as substring.

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, 2438869 + ... + 2698027.

Almost surely, 2^665636415232 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 665636415232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (678045491200).

665636415232 is an abundant number, since it is smaller than the sum of its proper divisors (690454567168).

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

665636415232 is a wasteful number, since it uses less digits than its factorization.

665636415232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259381 (or 259367 counting only the distinct ones).

The product of its digits is 4665600, while the sum is 49.

The spelling of 665636415232 in words is "six hundred sixty-five billion, six hundred thirty-six million, four hundred fifteen thousand, two hundred thirty-two".