8821421 has 12 divisors (see below), whose sum is σ = 10418688. Its totient is φ = 7445592.

The previous prime is 8821399. The next prime is 8821427. The reversal of 8821421 is 1241288.

8821421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 8821421 - 2¹⁰ = 8820397 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8821427) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1940 + ... + 4626.

It is an arithmetic number, because the mean of its divisors is an integer number (868224).

Almost surely, 2^8821421 is an apocalyptic number.

It is an amenable number.

8821421 is a deficient number, since it is larger than the sum of its proper divisors (1597267).

8821421 is a wasteful number, since it uses less digits than its factorization.

8821421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2768 (or 2761 counting only the distinct ones).

The product of its digits is 1024, while the sum is 26.

The square root of 8821421 is about 2970.0877091426. The cubic root of 8821421 is about 206.6234060798.

The spelling of 8821421 in words is "eight million, eight hundred twenty-one thousand, four hundred twenty-one".