665499408 has 160 divisors (see below), whose sum is σ = 2093008896. Its totient is φ = 177874944.

The previous prime is 665499389. The next prime is 665499421. The reversal of 665499408 is 804994566.

665499408 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 (51).

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, 1502035 + ... + 1502477.

Almost surely, 2^665499408 is an apocalyptic number.

665499408 is a gapful number since it is divisible by the number (68) 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 665499408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1046504448).

665499408 is an abundant number, since it is smaller than the sum of its proper divisors (1427509488).

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

665499408 is a wasteful number, since it uses less digits than its factorization.

665499408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 741 (or 735 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 51.

The square root of 665499408 is about 25797.2752049514. The cubic root of 665499408 is about 873.0703197005.

It can be divided in two parts, 66549 and 9408, that added together give a palindrome (75957).

The spelling of 665499408 in words is "six hundred sixty-five million, four hundred ninety-nine thousand, four hundred eight".