21916003 has 2 divisors, whose sum is σ = 21916004. Its totient is φ = 21916002.

The previous prime is 21916001. The next prime is 21916021. The reversal of 21916003 is 30061912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21916003 - 2¹ = 21916001 is a prime.

It is a super-2 number, since 2×21916003² = 960622374992018, which contains 22 as substring.

Together with 21916001, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21916001) 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, 10958001 + 10958002.

It is an arithmetic number, because the mean of its divisors is an integer number (10958002).

Almost surely, 2^21916003 is an apocalyptic number.

21916003 is a deficient number, since it is larger than the sum of its proper divisors (1).

21916003 is an equidigital number, since it uses as much as digits as its factorization.

21916003 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 21916003 is about 4681.4530863825. The cubic root of 21916003 is about 279.8468677978.

Adding to 21916003 its reverse (30061912), we get a palindrome (51977915).

The spelling of 21916003 in words is "twenty-one million, nine hundred sixteen thousand, three".