1640668800 has 384 divisors, whose sum is σ = 5767488000. Its totient is φ = 409190400.

The previous prime is 1640668739. The next prime is 1640668817. The reversal of 1640668800 is 88660461.

It is a tau number, because it is divible by the number of its divisors (384).

It is a super-2 number, since 2×1640668800² = 5383588222586880000, which contains 22 as substring.

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 47 ways as a sum of consecutive naturals, for example, 11011126 + ... + 11011274.

It is an arithmetic number, because the mean of its divisors is an integer number (15019500).

Almost surely, 2^1640668800 is an apocalyptic number.

1640668800 is a gapful number since it is divisible by the number (10) 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 1640668800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2883744000).

1640668800 is an abundant number, since it is smaller than the sum of its proper divisors (4126819200).

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

1640668800 is a wasteful number, since it uses less digits than its factorization.

1640668800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244 (or 227 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 39.

The square root of 1640668800 is about 40505.1700403788. The cubic root of 1640668800 is about 1179.4339907316.

The spelling of 1640668800 in words is "one billion, six hundred forty million, six hundred sixty-eight thousand, eight hundred".