1816660800 has 504 divisors, whose sum is σ = 7042096152. Its totient is φ = 442368000.

The previous prime is 1816660789. The next prime is 1816660801. The reversal of 1816660800 is 80666181.

It can be written as a sum of positive squares in 12 ways, for example, as 1301189184 + 515471616 = 36072^2 + 22704^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1816660801) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 10036710 + ... + 10036890.

It is an arithmetic number, because the mean of its divisors is an integer number (13972413).

Almost surely, 2^1816660800 is an apocalyptic number.

1816660800 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 1816660800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3521048076).

1816660800 is an abundant number, since it is smaller than the sum of its proper divisors (5225435352).

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

1816660800 is a wasteful number, since it uses less digits than its factorization.

1816660800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 267 (or 249 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 1816660800 is about 42622.3040203131. The cubic root of 1816660800 is about 1220.1820027673.

The spelling of 1816660800 in words is "one billion, eight hundred sixteen million, six hundred sixty thousand, eight hundred".