820812384 has 72 divisors (see below), whose sum is σ = 2667646800. Its totient is φ = 234517248.

The previous prime is 820812383. The next prime is 820812397. The reversal of 820812384 is 483218028.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (72).

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 (820812383) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 201559 + ... + 205590.

It is an arithmetic number, because the mean of its divisors is an integer number (37050650).

Almost surely, 2^820812384 is an apocalyptic number.

820812384 is a gapful number since it is divisible by the number (84) formed by its first and last digit.

It is an amenable number.

820812384 is an abundant number, since it is smaller than the sum of its proper divisors (1846834416).

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

820812384 is a wasteful number, since it uses less digits than its factorization.

820812384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407172 (or 407161 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 36.

The square root of 820812384 is about 28649.8234549534. The cubic root of 820812384 is about 936.2991592503.

The spelling of 820812384 in words is "eight hundred twenty million, eight hundred twelve thousand, three hundred eighty-four".