819997560 has 128 divisors (see below), whose sum is σ = 2744193600. Its totient is φ = 217797120.

The previous prime is 819997553. The next prime is 819997583. The reversal of 819997560 is 65799918.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 819997497 and 819997506.

It is a congruent number.

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 31 ways as a sum of consecutive naturals, for example, 297790 + ... + 300530.

Almost surely, 2^819997560 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 819997560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1372096800).

819997560 is an abundant number, since it is smaller than the sum of its proper divisors (1924196040).

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

819997560 is a wasteful number, since it uses less digits than its factorization.

819997560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3038 (or 3028 counting only the distinct ones).

The product of its (nonzero) digits is 1224720, while the sum is 54.

The square root of 819997560 is about 28635.5995222730. The cubic root of 819997560 is about 935.9892339327.

The spelling of 819997560 in words is "eight hundred nineteen million, nine hundred ninety-seven thousand, five hundred sixty".