665246400 has 336 divisors, whose sum is σ = 2687994624. Its totient is φ = 140267520.

The previous prime is 665246377. The next prime is 665246401. The reversal of 665246400 is 4642566.

665246400 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (336).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665246401) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 436039 + ... + 437561.

It is an arithmetic number, because the mean of its divisors is an integer number (7999984).

Almost surely, 2^665246400 is an apocalyptic number.

665246400 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 665246400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1343997312).

665246400 is an abundant number, since it is smaller than the sum of its proper divisors (2022748224).

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

665246400 is a wasteful number, since it uses less digits than its factorization.

665246400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1568 (or 1553 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 33.

The square root of 665246400 is about 25792.3709650741. The cubic root of 665246400 is about 872.9596650695.

Adding to 665246400 its reverse (4642566), we get a palindrome (669888966).

The spelling of 665246400 in words is "six hundred sixty-five million, two hundred forty-six thousand, four hundred".