820974784 has 56 divisors (see below), whose sum is σ = 1865538560. Its totient is φ = 351150336.

The previous prime is 820974779. The next prime is 820974797. The reversal of 820974784 is 487479028.

It is a tau number, because it is divible by the number of its divisors (56).

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 270427 + ... + 273445.

Almost surely, 2^820974784 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 820974784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (932769280).

820974784 is an abundant number, since it is smaller than the sum of its proper divisors (1044563776).

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

820974784 is a wasteful number, since it uses less digits than its factorization.

820974784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3645 (or 3635 counting only the distinct ones).

The product of its (nonzero) digits is 903168, while the sum is 49.

The square root of 820974784 is about 28652.6575381761. The cubic root of 820974784 is about 936.3609049709.

The spelling of 820974784 in words is "eight hundred twenty million, nine hundred seventy-four thousand, seven hundred eighty-four".