21842903 has 2 divisors, whose sum is σ = 21842904. Its totient is φ = 21842902.

The previous prime is 21842881. The next prime is 21842917. The reversal of 21842903 is 30924812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21842903 - 2¹⁰ = 21841879 is a prime.

It is a super-2 number, since 2×21842903² = 954224822934818, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21842963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10921451 + 10921452.

It is an arithmetic number, because the mean of its divisors is an integer number (10921452).

Almost surely, 2^21842903 is an apocalyptic number.

21842903 is a deficient number, since it is larger than the sum of its proper divisors (1).

21842903 is an equidigital number, since it uses as much as digits as its factorization.

21842903 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 21842903 is about 4673.6391602262. The cubic root of 21842903 is about 279.5353816724.

The spelling of 21842903 in words is "twenty-one million, eight hundred forty-two thousand, nine hundred three".