21814369 has 2 divisors, whose sum is σ = 21814370. Its totient is φ = 21814368.

The previous prime is 21814367. The next prime is 21814379. The reversal of 21814369 is 96341812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17766225 + 4048144 = 4215^2 + 2012^2 .

It is a cyclic number.

It is not a de Polignac number, because 21814369 - 2¹ = 21814367 is a prime.

It is a super-2 number, since 2×21814369² = 951733389736322, which contains 22 as substring.

Together with 21814367, it forms a pair of twin primes.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (21814363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10907184 + 10907185.

It is an arithmetic number, because the mean of its divisors is an integer number (10907185).

Almost surely, 2^21814369 is an apocalyptic number.

It is an amenable number.

21814369 is a deficient number, since it is larger than the sum of its proper divisors (1).

21814369 is an equidigital number, since it uses as much as digits as its factorization.

21814369 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10368, while the sum is 34.

The square root of 21814369 is about 4670.5855093339. The cubic root of 21814369 is about 279.4136069811.

The spelling of 21814369 in words is "twenty-one million, eight hundred fourteen thousand, three hundred sixty-nine".