18222421 has 8 divisors (see below), whose sum is σ = 21021120. Its totient is φ = 15472608.

The previous prime is 18222367. The next prime is 18222427. The reversal of 18222421 is 12422281.

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 18222421 - 2²¹ = 16125269 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18222392 and 18222401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18222427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11416 + ... + 12913.

It is an arithmetic number, because the mean of its divisors is an integer number (2627640).

Almost surely, 2^18222421 is an apocalyptic number.

It is an amenable number.

18222421 is a deficient number, since it is larger than the sum of its proper divisors (2798699).

18222421 is a wasteful number, since it uses less digits than its factorization.

18222421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24443.

The product of its digits is 512, while the sum is 22.

The square root of 18222421 is about 4268.7727744634. The cubic root of 18222421 is about 263.1491826161.

The spelling of 18222421 in words is "eighteen million, two hundred twenty-two thousand, four hundred twenty-one".