21344903 has 2 divisors, whose sum is σ = 21344904. Its totient is φ = 21344902.

The previous prime is 21344857. The next prime is 21344929. The reversal of 21344903 is 30944312.

It is an a-pointer prime, because the next prime (21344929) can be obtained adding 21344903 to its sum of digits (26).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21344903 - 2⁶ = 21344839 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21344933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10672451 + 10672452.

It is an arithmetic number, because the mean of its divisors is an integer number (10672452).

Almost surely, 2^21344903 is an apocalyptic number.

21344903 is a deficient number, since it is larger than the sum of its proper divisors (1).

21344903 is an equidigital number, since it uses as much as digits as its factorization.

21344903 is an evil number, because the sum of its binary digits is even.

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

The square root of 21344903 is about 4620.0544369087. The cubic root of 21344903 is about 277.3946379220.

The spelling of 21344903 in words is "twenty-one million, three hundred forty-four thousand, nine hundred three".