21038249 has 2 divisors, whose sum is σ = 21038250. Its totient is φ = 21038248.

The previous prime is 21038219. The next prime is 21038267. The reversal of 21038249 is 94283012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17682025 + 3356224 = 4205^2 + 1832^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21038249 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21038209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10519124 + 10519125.

It is an arithmetic number, because the mean of its divisors is an integer number (10519125).

Almost surely, 2^21038249 is an apocalyptic number.

It is an amenable number.

21038249 is a deficient number, since it is larger than the sum of its proper divisors (1).

21038249 is an equidigital number, since it uses as much as digits as its factorization.

21038249 is an evil number, because the sum of its binary digits is even.

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

The square root of 21038249 is about 4586.7471044303. The cubic root of 21038249 is about 276.0598177775.

The spelling of 21038249 in words is "twenty-one million, thirty-eight thousand, two hundred forty-nine".