816747580 has 72 divisors (see below), whose sum is σ = 1891777104. Its totient is φ = 295975680.

The previous prime is 816747563. The next prime is 816747587. The reversal of 816747580 is 85747618.

It is a self number, because there is not a number n which added to its sum of digits gives 816747580.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816747587) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1323432 + ... + 1324048.

It is an arithmetic number, because the mean of its divisors is an integer number (26274682).

Almost surely, 2^816747580 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 816747580, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (945888552).

816747580 is an abundant number, since it is smaller than the sum of its proper divisors (1075029524).

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

816747580 is a wasteful number, since it uses less digits than its factorization.

816747580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1195 (or 1182 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 46.

The square root of 816747580 is about 28578.7959858354. The cubic root of 816747580 is about 934.7510294427.

The spelling of 816747580 in words is "eight hundred sixteen million, seven hundred forty-seven thousand, five hundred eighty".