821889473 has 8 divisors (see below), whose sum is σ = 847797480. Its totient is φ = 796176000.

The previous prime is 821889443. The next prime is 821889491. The reversal of 821889473 is 374988128.

It can be written as a sum of positive squares in 4 ways, for example, as 591851584 + 230037889 = 24328^2 + 15167^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 821889473 - 2¹⁴ = 821873089 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (821889413) 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, 40028 + ... + 56973.

It is an arithmetic number, because the mean of its divisors is an integer number (105974685).

Almost surely, 2^821889473 is an apocalyptic number.

It is an amenable number.

821889473 is a deficient number, since it is larger than the sum of its proper divisors (25908007).

821889473 is a wasteful number, since it uses less digits than its factorization.

821889473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97267.

The product of its digits is 774144, while the sum is 50.

The square root of 821889473 is about 28668.6147729534. The cubic root of 821889473 is about 936.7085247157.

The spelling of 821889473 in words is "eight hundred twenty-one million, eight hundred eighty-nine thousand, four hundred seventy-three".