660200400 has 90 divisors (see below), whose sum is σ = 2291091270. Its totient is φ = 176052480.

The previous prime is 660200381. The next prime is 660200407. The reversal of 660200400 is 4002066.

660200400 is a `hidden beast` number, since 6 + 60 + 200 + 400 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 2585664 + 657614736 = 1608^2 + 25644^2 .

It is a tau number, because it is divible by the number of its divisors (90).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660200407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 88095 + ... + 95294.

Almost surely, 2^660200400 is an apocalyptic number.

660200400 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

660200400 is an abundant number, since it is smaller than the sum of its proper divisors (1630890870).

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

660200400 is a wasteful number, since it uses less digits than its factorization.

660200400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183413 (or 183399 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 660200400 is about 25694.3651410188. The cubic root of 660200400 is about 870.7468814208.

Adding to 660200400 its reverse (4002066), we get a palindrome (664202466).

The spelling of 660200400 in words is "six hundred sixty million, two hundred thousand, four hundred".