21343013 has 2 divisors, whose sum is σ = 21343014. Its totient is φ = 21343012.

The previous prime is 21343009. The next prime is 21343019. The reversal of 21343013 is 31034312.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16176484 + 5166529 = 4022^2 + 2273^2 .

It is a cyclic number.

It is not a de Polignac number, because 21343013 - 2² = 21343009 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21342982 and 21343000.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21343019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10671506 + 10671507.

It is an arithmetic number, because the mean of its divisors is an integer number (10671507).

Almost surely, 2^21343013 is an apocalyptic number.

It is an amenable number.

21343013 is a deficient number, since it is larger than the sum of its proper divisors (1).

21343013 is an equidigital number, since it uses as much as digits as its factorization.

21343013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 17.

The square root of 21343013 is about 4619.8498893362. The cubic root of 21343013 is about 277.3864503102.

Adding to 21343013 its reverse (31034312), we get a palindrome (52377325).

The spelling of 21343013 in words is "twenty-one million, three hundred forty-three thousand, thirteen".