665372880 has 160 divisors (see below), whose sum is σ = 2320744320. Its totient is φ = 177386112.

The previous prime is 665372867. The next prime is 665372909. The reversal of 665372880 is 88273566.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 173059 + ... + 176861.

It is an arithmetic number, because the mean of its divisors is an integer number (14504652).

Almost surely, 2^665372880 is an apocalyptic number.

665372880 is a gapful number since it is divisible by the number (60) 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 665372880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1160372160).

665372880 is an abundant number, since it is smaller than the sum of its proper divisors (1655371440).

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

665372880 is an equidigital number, since it uses as much as digits as its factorization.

665372880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3837 (or 3813 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The square root of 665372880 is about 25794.8227363554. The cubic root of 665372880 is about 873.0149853948.

The spelling of 665372880 in words is "six hundred sixty-five million, three hundred seventy-two thousand, eight hundred eighty".