821920867 has 8 divisors (see below), whose sum is σ = 874101200. Its totient is φ = 770632704.

The previous prime is 821920861. The next prime is 821920889. The reversal of 821920867 is 768029128.

821920867 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 821920867 - 2²⁷ = 687703139 is a prime.

It is a super-2 number, since 2×821920867² = 1351107823220063378, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (821920861) 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, 221142 + ... + 224827.

It is an arithmetic number, because the mean of its divisors is an integer number (109262650).

Almost surely, 2^821920867 is an apocalyptic number.

821920867 is a deficient number, since it is larger than the sum of its proper divisors (52180333).

821920867 is a wasteful number, since it uses less digits than its factorization.

821920867 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 446085.

The product of its (nonzero) digits is 96768, while the sum is 43.

The square root of 821920867 is about 28669.1623002836. The cubic root of 821920867 is about 936.7204511583.

The spelling of 821920867 in words is "eight hundred twenty-one million, nine hundred twenty thousand, eight hundred sixty-seven".