21342329 has 2 divisors, whose sum is σ = 21342330. Its totient is φ = 21342328.

The previous prime is 21342311. The next prime is 21342331. The reversal of 21342329 is 92324312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21160000 + 182329 = 4600^2 + 427^2 .

It is a cyclic number.

It is not a de Polignac number, because 21342329 - 2¹⁶ = 21276793 is a prime.

Together with 21342331, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21342298 and 21342307.

It is not a weakly prime, because it can be changed into another prime (21342359) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10671164 + 10671165.

It is an arithmetic number, because the mean of its divisors is an integer number (10671165).

Almost surely, 2^21342329 is an apocalyptic number.

It is an amenable number.

21342329 is a deficient number, since it is larger than the sum of its proper divisors (1).

21342329 is an equidigital number, since it uses as much as digits as its factorization.

21342329 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2592, while the sum is 26.

The square root of 21342329 is about 4619.7758603638. The cubic root of 21342329 is about 277.3834870554.

The spelling of 21342329 in words is "twenty-one million, three hundred forty-two thousand, three hundred twenty-nine".