665136516 has 72 divisors (see below), whose sum is σ = 1725403680. Its totient is φ = 199253120.

The previous prime is 665136491. The next prime is 665136523. The reversal of 665136516 is 615631566.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 126655 + ... + 131801.

It is an arithmetic number, because the mean of its divisors is an integer number (23963940).

Almost surely, 2^665136516 is an apocalyptic number.

665136516 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 665136516, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (862701840).

665136516 is an abundant number, since it is smaller than the sum of its proper divisors (1060267164).

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

665136516 is a wasteful number, since it uses less digits than its factorization.

665136516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5265 (or 5252 counting only the distinct ones).

The product of its digits is 97200, while the sum is 39.

The square root of 665136516 is about 25790.2407123315. The cubic root of 665136516 is about 872.9115978762.

The spelling of 665136516 in words is "six hundred sixty-five million, one hundred thirty-six thousand, five hundred sixteen".