21845249 has 2 divisors, whose sum is σ = 21845250. Its totient is φ = 21845248.

The previous prime is 21845237. The next prime is 21845261. The reversal of 21845249 is 94254812.

It is a balanced prime because it is at equal distance from previous prime (21845237) and next prime (21845261).

It can be written as a sum of positive squares in only one way, i.e., 16974400 + 4870849 = 4120^2 + 2207^2 .

It is a cyclic number.

It is not a de Polignac number, because 21845249 - 2⁴ = 21845233 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21848249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10922624 + 10922625.

It is an arithmetic number, because the mean of its divisors is an integer number (10922625).

Almost surely, 2^21845249 is an apocalyptic number.

It is an amenable number.

21845249 is a deficient number, since it is larger than the sum of its proper divisors (1).

21845249 is an equidigital number, since it uses as much as digits as its factorization.

21845249 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23040, while the sum is 35.

The square root of 21845249 is about 4673.8901356365. The cubic root of 21845249 is about 279.5453889888.

The spelling of 21845249 in words is "twenty-one million, eight hundred forty-five thousand, two hundred forty-nine".