21003107 has 2 divisors, whose sum is σ = 21003108. Its totient is φ = 21003106.

The previous prime is 21003097. The next prime is 21003121. The reversal of 21003107 is 70130012.

It is an a-pointer prime, because the next prime (21003121) can be obtained adding 21003107 to its sum of digits (14).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21003107 - 2¹⁰ = 21002083 is a prime.

It is a super-3 number, since 3×21003107³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21003091 and 21003100.

It is not a weakly prime, because it can be changed into another prime (21003707) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501553 + 10501554.

It is an arithmetic number, because the mean of its divisors is an integer number (10501554).

Almost surely, 2^21003107 is an apocalyptic number.

21003107 is a deficient number, since it is larger than the sum of its proper divisors (1).

21003107 is an equidigital number, since it uses as much as digits as its factorization.

21003107 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 42, while the sum is 14.

The square root of 21003107 is about 4582.9146839102. The cubic root of 21003107 is about 275.9060232805.

Adding to 21003107 its reverse (70130012), we get a palindrome (91133119).

The spelling of 21003107 in words is "twenty-one million, three thousand, one hundred seven".