21838469 has 2 divisors, whose sum is σ = 21838470. Its totient is φ = 21838468.

The previous prime is 21838457. The next prime is 21838501. The reversal of 21838469 is 96483812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12687844 + 9150625 = 3562^2 + 3025^2 .

It is a cyclic number.

It is not a de Polignac number, because 21838469 - 2²⁴ = 5061253 is a prime.

It is a super-2 number, since 2×21838469² = 953837456527922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21838669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10919234 + 10919235.

It is an arithmetic number, because the mean of its divisors is an integer number (10919235).

Almost surely, 2^21838469 is an apocalyptic number.

It is an amenable number.

21838469 is a deficient number, since it is larger than the sum of its proper divisors (1).

21838469 is an equidigital number, since it uses as much as digits as its factorization.

21838469 is an evil number, because the sum of its binary digits is even.

The product of its digits is 82944, while the sum is 41.

The square root of 21838469 is about 4673.1647734699. The cubic root of 21838469 is about 279.5164656311.

The spelling of 21838469 in words is "twenty-one million, eight hundred thirty-eight thousand, four hundred sixty-nine".