818681388 has 48 divisors (see below), whose sum is σ = 2242162944. Its totient is φ = 227586240.

The previous prime is 818681377. The next prime is 818681419. The reversal of 818681388 is 883186818.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 818681388.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 128598 + ... + 134813.

It is an arithmetic number, because the mean of its divisors is an integer number (46711728).

Almost surely, 2^818681388 is an apocalyptic number.

It is an amenable number.

818681388 is an abundant number, since it is smaller than the sum of its proper divisors (1423481556).

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

818681388 is a wasteful number, since it uses less digits than its factorization.

818681388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263462 (or 263460 counting only the distinct ones).

The product of its digits is 589824, while the sum is 51.

The square root of 818681388 is about 28612.6088988753. The cubic root of 818681388 is about 935.4881826340.

The spelling of 818681388 in words is "eight hundred eighteen million, six hundred eighty-one thousand, three hundred eighty-eight".