665615016 has 128 divisors (see below), whose sum is σ = 2024726400. Its totient is φ = 200931840.

The previous prime is 665615003. The next prime is 665615023. The reversal of 665615016 is 610516566.

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

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1085526 + ... + 1086138.

It is an arithmetic number, because the mean of its divisors is an integer number (15818175).

Almost surely, 2^665615016 is an apocalyptic number.

665615016 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 665615016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1012363200).

665615016 is an abundant number, since it is smaller than the sum of its proper divisors (1359111384).

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

665615016 is a wasteful number, since it uses less digits than its factorization.

665615016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1096 (or 1086 counting only the distinct ones).

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

The square root of 665615016 is about 25799.5158094101. The cubic root of 665615016 is about 873.1208722471.

The spelling of 665615016 in words is "six hundred sixty-five million, six hundred fifteen thousand, sixteen".