820021519444 has 12 divisors (see below), whose sum is σ = 1435044969568. Its totient is φ = 410008671000.

The previous prime is 820021519423. The next prime is 820021519463. The reversal of 820021519444 is 444915120028.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 820021519397 and 820021519406.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 657049 + ... + 1439359.

Almost surely, 2^820021519444 is an apocalyptic number.

It is an amenable number.

820021519444 is a deficient number, since it is larger than the sum of its proper divisors (615023450124).

820021519444 is a wasteful number, since it uses less digits than its factorization.

820021519444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1044366 (or 1044364 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 40.

The spelling of 820021519444 in words is "eight hundred twenty billion, twenty-one million, five hundred nineteen thousand, four hundred forty-four".