816998400 has 360 divisors, whose sum is σ = 3041348310. Its totient is φ = 216760320.

The previous prime is 816998389. The next prime is 816998449. The reversal of 816998400 is 4899618.

It can be written as a sum of positive squares in 3 ways, for example, as 780420096 + 36578304 = 27936^2 + 6048^2 .

It is a tau number, because it is divible by the number of its divisors (360).

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

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 4147102 + ... + 4147298.

Almost surely, 2^816998400 is an apocalyptic number.

816998400 is a gapful number since it is divisible by the number (80) 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 816998400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1520674155).

816998400 is an abundant number, since it is smaller than the sum of its proper divisors (2224349910).

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

816998400 is a wasteful number, since it uses less digits than its factorization.

816998400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241 (or 207 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 45.

The square root of 816998400 is about 28583.1838674421. The cubic root of 816998400 is about 934.8467057827.

The spelling of 816998400 in words is "eight hundred sixteen million, nine hundred ninety-eight thousand, four hundred".