820551384 has 80 divisors (see below), whose sum is σ = 2302654200. Its totient is φ = 272999808.

The previous prime is 820551377. The next prime is 820551397. The reversal of 820551384 is 483155028.

It is a happy number.

820551384 is a `hidden beast` number, since 8 + 20 + 551 + 3 + 84 = 666.

820551384 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 509172 + ... + 510780.

Almost surely, 2^820551384 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 820551384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1151327100).

820551384 is an abundant number, since it is smaller than the sum of its proper divisors (1482102816).

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

820551384 is a wasteful number, since it uses less digits than its factorization.

820551384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2414 (or 2401 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 36.

The square root of 820551384 is about 28645.2680909081. The cubic root of 820551384 is about 936.1999079916.

The spelling of 820551384 in words is "eight hundred twenty million, five hundred fifty-one thousand, three hundred eighty-four".