820934784 has 128 divisors (see below), whose sum is σ = 2506752000. Its totient is φ = 264176640.

The previous prime is 820934783. The next prime is 820934789. The reversal of 820934784 is 487439028.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×820934784² = 1347867839162253312, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (820934783) 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 15 ways as a sum of consecutive naturals, for example, 96129 + ... + 104319.

It is an arithmetic number, because the mean of its divisors is an integer number (19584000).

Almost surely, 2^820934784 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 820934784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1253376000).

820934784 is an abundant number, since it is smaller than the sum of its proper divisors (1685817216).

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

820934784 is a wasteful number, since it uses less digits than its factorization.

820934784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8243 (or 8225 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 45.

The square root of 820934784 is about 28651.9595141414. The cubic root of 820934784 is about 936.3456974212.

The spelling of 820934784 in words is "eight hundred twenty million, nine hundred thirty-four thousand, seven hundred eighty-four".