21343601 has 2 divisors, whose sum is σ = 21343602. Its totient is φ = 21343600.

The previous prime is 21343583. The next prime is 21343603. The reversal of 21343601 is 10634312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20295025 + 1048576 = 4505^2 + 1024^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21343601 is a prime.

Together with 21343603, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_1350317 and since 21343601 and 1350317 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (21343603) 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, 10671800 + 10671801.

It is an arithmetic number, because the mean of its divisors is an integer number (10671801).

Almost surely, 2^21343601 is an apocalyptic number.

It is an amenable number.

21343601 is a deficient number, since it is larger than the sum of its proper divisors (1).

21343601 is an equidigital number, since it uses as much as digits as its factorization.

21343601 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 21343601 is about 4619.9135273293. The cubic root of 21343601 is about 277.3889976190.

Adding to 21343601 its reverse (10634312), we get a palindrome (31977913).

The spelling of 21343601 in words is "twenty-one million, three hundred forty-three thousand, six hundred one".