8418821 has 4 divisors (see below), whose sum is σ = 8433612. Its totient is φ = 8404032.

The previous prime is 8418803. The next prime is 8418847. The reversal of 8418821 is 1288148.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7230721 + 1188100 = 2689^2 + 1090^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8418821 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8418521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6506 + ... + 7691.

It is an arithmetic number, because the mean of its divisors is an integer number (2108403).

Almost surely, 2^8418821 is an apocalyptic number.

It is an amenable number.

8418821 is a deficient number, since it is larger than the sum of its proper divisors (14791).

8418821 is a wasteful number, since it uses less digits than its factorization.

8418821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14790.

The product of its digits is 4096, while the sum is 32.

The square root of 8418821 is about 2901.5204634812. The cubic root of 8418821 is about 203.4309803024.

The spelling of 8418821 in words is "eight million, four hundred eighteen thousand, eight hundred twenty-one".