21414389 has 2 divisors, whose sum is σ = 21414390. Its totient is φ = 21414388.

The previous prime is 21414377. The next prime is 21414391. The reversal of 21414389 is 98341412.

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., 20295025 + 1119364 = 4505^2 + 1058^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21414389 is a prime.

Together with 21414391, it forms a pair of twin primes.

It is a Chen prime.

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

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21414089) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10707194 + 10707195.

It is an arithmetic number, because the mean of its divisors is an integer number (10707195).

Almost surely, 2^21414389 is an apocalyptic number.

It is an amenable number.

21414389 is a deficient number, since it is larger than the sum of its proper divisors (1).

21414389 is an equidigital number, since it uses as much as digits as its factorization.

21414389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6912, while the sum is 32.

The square root of 21414389 is about 4627.5683679444. The cubic root of 21414389 is about 277.6953211909.

The spelling of 21414389 in words is "twenty-one million, four hundred fourteen thousand, three hundred eighty-nine".