665424760 has 128 divisors (see below), whose sum is σ = 2010355200. Its totient is φ = 191439360.

The previous prime is 665424737. The next prime is 665424763. The reversal of 665424760 is 67424566.

It is a super-2 number, since 2×665424760² = 885580222442115200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665424763) 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, 31731 + ... + 48349.

It is an arithmetic number, because the mean of its divisors is an integer number (15705900).

Almost surely, 2^665424760 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 665424760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1005177600).

665424760 is an abundant number, since it is smaller than the sum of its proper divisors (1344930440).

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

665424760 is a wasteful number, since it uses less digits than its factorization.

665424760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16661 (or 16657 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 40.

The square root of 665424760 is about 25795.8283449088. The cubic root of 665424760 is about 873.0376748479.

The spelling of 665424760 in words is "six hundred sixty-five million, four hundred twenty-four thousand, seven hundred sixty".