821713872 has 40 divisors (see below), whose sum is σ = 2426013376. Its totient is φ = 234775296.

The previous prime is 821713817. The next prime is 821713873. The reversal of 821713872 is 278317128.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 821713872.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821713873) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1222453 + ... + 1223124.

Almost surely, 2^821713872 is an apocalyptic number.

It is an amenable number.

821713872 is an abundant number, since it is smaller than the sum of its proper divisors (1604299504).

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

821713872 is a wasteful number, since it uses less digits than its factorization.

821713872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2445595 (or 2445589 counting only the distinct ones).

The product of its digits is 37632, while the sum is 39.

The square root of 821713872 is about 28665.5520093369. The cubic root of 821713872 is about 936.6418090664.

The spelling of 821713872 in words is "eight hundred twenty-one million, seven hundred thirteen thousand, eight hundred seventy-two".