665116056 has 128 divisors (see below), whose sum is σ = 2029478400. Its totient is φ = 200154240.

The previous prime is 665116051. The next prime is 665116061. The reversal of 665116056 is 650611566.

It is an interprime number because it is at equal distance from previous prime (665116051) and next prime (665116061).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 665116056.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665116051) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 372141 + ... + 373923.

It is an arithmetic number, because the mean of its divisors is an integer number (15855300).

Almost surely, 2^665116056 is an apocalyptic number.

665116056 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665116056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1014739200).

665116056 is an abundant number, since it is smaller than the sum of its proper divisors (1364362344).

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

665116056 is a wasteful number, since it uses less digits than its factorization.

665116056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1966 (or 1956 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 665116056 is about 25789.8440476091. The cubic root of 665116056 is about 872.9026473555.

The spelling of 665116056 in words is "six hundred sixty-five million, one hundred sixteen thousand, fifty-six".