665740824 has 128 divisors (see below), whose sum is σ = 1949875200. Its totient is φ = 185495040.

The previous prime is 665740807. The next prime is 665740847. The reversal of 665740824 is 428047566.

665740824 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

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, 1711222 + ... + 1711610.

It is an arithmetic number, because the mean of its divisors is an integer number (15233400).

Almost surely, 2^665740824 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 665740824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (974937600).

665740824 is an abundant number, since it is smaller than the sum of its proper divisors (1284134376).

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

665740824 is a wasteful number, since it uses less digits than its factorization.

665740824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 633 (or 629 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 42.

The square root of 665740824 is about 25801.9538795030. The cubic root of 665740824 is about 873.1758783533.

The spelling of 665740824 in words is "six hundred sixty-five million, seven hundred forty thousand, eight hundred twenty-four".