820309081944 has 128 divisors (see below), whose sum is σ = 2335015226880. Its totient is φ = 237939686400.

The previous prime is 820309081937. The next prime is 820309082011. The reversal of 820309081944 is 449180903028.

It is a junction number, because it is equal to n+sod(n) for n = 820309081893 and 820309081902.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 141292 + ... + 1288635.

It is an arithmetic number, because the mean of its divisors is an integer number (18242306460).

Almost surely, 2^820309081944 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 820309081944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1167507613440).

820309081944 is an abundant number, since it is smaller than the sum of its proper divisors (1514706144936).

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

820309081944 is a wasteful number, since it uses less digits than its factorization.

820309081944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1430041 (or 1430037 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 48.

The spelling of 820309081944 in words is "eight hundred twenty billion, three hundred nine million, eighty-one thousand, nine hundred forty-four".