22018821 has 16 divisors (see below), whose sum is σ = 32417280. Its totient is φ = 13182320.

The previous prime is 22018819. The next prime is 22018847. The reversal of 22018821 is 12881022.

It is a cyclic number.

It is not a de Polignac number, because 22018821 - 2¹ = 22018819 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 22018791 and 22018800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22018421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1281 + ... + 6758.

It is an arithmetic number, because the mean of its divisors is an integer number (2026080).

Almost surely, 2^22018821 is an apocalyptic number.

It is an amenable number.

22018821 is a deficient number, since it is larger than the sum of its proper divisors (10398459).

22018821 is a wasteful number, since it uses less digits than its factorization.

22018821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8136.

The product of its (nonzero) digits is 512, while the sum is 24.

The square root of 22018821 is about 4692.4216562453. The cubic root of 22018821 is about 280.2838151117.

Adding to 22018821 its reverse (12881022), we get a palindrome (34899843).

The spelling of 22018821 in words is "twenty-two million, eighteen thousand, eight hundred twenty-one".