669981600 has 108 divisors (see below), whose sum is σ = 2362548006. Its totient is φ = 178659840.

The previous prime is 669981593. The next prime is 669981601. The reversal of 669981600 is 6189966.

It can be written as a sum of positive squares in 3 ways, for example, as 617621904 + 52359696 = 24852^2 + 7236^2 .

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

It is not an unprimeable number, because it can be changed into a prime (669981601) 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, 39327 + ... + 53726.

Almost surely, 2^669981600 is an apocalyptic number.

669981600 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

669981600 is an abundant number, since it is smaller than the sum of its proper divisors (1692566406).

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

669981600 is a wasteful number, since it uses less digits than its factorization.

669981600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93079 (or 93063 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The square root of 669981600 is about 25884.0027816410. The cubic root of 669981600 is about 875.0260019484.

The spelling of 669981600 in words is "six hundred sixty-nine million, nine hundred eighty-one thousand, six hundred".