818644320 has 480 divisors, whose sum is σ = 3211905312. Its totient is φ = 195084288.

The previous prime is 818644303. The next prime is 818644327. The reversal of 818644320 is 23446818.

818644320 is a `hidden beast` number, since 8 + 1 + 8 + 644 + 3 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

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 (818644327) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 7244584 + ... + 7244696.

Almost surely, 2^818644320 is an apocalyptic number.

818644320 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 818644320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1605952656).

818644320 is an abundant number, since it is smaller than the sum of its proper divisors (2393260992).

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

818644320 is a wasteful number, since it uses less digits than its factorization.

818644320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196 (or 179 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 818644320 is about 28611.9611351616. The cubic root of 818644320 is about 935.4740635071.

The spelling of 818644320 in words is "eight hundred eighteen million, six hundred forty-four thousand, three hundred twenty".