665395072 has 64 divisors (see below), whose sum is σ = 1382618160. Its totient is φ = 318689280.

The previous prime is 665395063. The next prime is 665395091. The reversal of 665395072 is 270593566.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (43).

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, 290572 + ... + 292852.

Almost surely, 2^665395072 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 665395072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (691309080).

665395072 is an abundant number, since it is smaller than the sum of its proper divisors (717223088).

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

665395072 is a wasteful number, since it uses less digits than its factorization.

665395072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2391 (or 2379 counting only the distinct ones).

The product of its (nonzero) digits is 340200, while the sum is 43.

The square root of 665395072 is about 25795.2528966087. The cubic root of 665395072 is about 873.0246910971.

The spelling of 665395072 in words is "six hundred sixty-five million, three hundred ninety-five thousand, seventy-two".