21003299 has 2 divisors, whose sum is σ = 21003300. Its totient is φ = 21003298.

The previous prime is 21003293. The next prime is 21003329. The reversal of 21003299 is 99230012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21003299 - 2¹² = 20999203 is a prime.

It is a super-2 number, since 2×21003299² = 882277137766802, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21003293) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501649 + 10501650.

It is an arithmetic number, because the mean of its divisors is an integer number (10501650).

Almost surely, 2^21003299 is an apocalyptic number.

21003299 is a deficient number, since it is larger than the sum of its proper divisors (1).

21003299 is an equidigital number, since it uses as much as digits as its factorization.

21003299 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 21003299 is about 4582.9356312303. The cubic root of 21003299 is about 275.9068640100.

The spelling of 21003299 in words is "twenty-one million, three thousand, two hundred ninety-nine".