22402421 has 2 divisors, whose sum is σ = 22402422. Its totient is φ = 22402420.

The previous prime is 22402399. The next prime is 22402423. The reversal of 22402421 is 12420422.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22221796 + 180625 = 4714^2 + 425^2 .

It is a cyclic number.

It is not a de Polignac number, because 22402421 - 2¹⁰ = 22401397 is a prime.

It is a super-2 number, since 2×22402421² = 1003736933322482, which contains 22 as substring.

Together with 22402423, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 22402421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22402423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11201210 + 11201211.

It is an arithmetic number, because the mean of its divisors is an integer number (11201211).

Almost surely, 2^22402421 is an apocalyptic number.

It is an amenable number.

22402421 is a deficient number, since it is larger than the sum of its proper divisors (1).

22402421 is an equidigital number, since it uses as much as digits as its factorization.

22402421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 256, while the sum is 17.

The square root of 22402421 is about 4733.1195843756. The cubic root of 22402421 is about 281.9021045776.

Adding to 22402421 its reverse (12420422), we get a palindrome (34822843).

The spelling of 22402421 in words is "twenty-two million, four hundred two thousand, four hundred twenty-one".