21848251 has 2 divisors, whose sum is σ = 21848252. Its totient is φ = 21848250.

The previous prime is 21848249. The next prime is 21848261. The reversal of 21848251 is 15284812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21848251 - 2¹ = 21848249 is a prime.

Together with 21848249, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21848221) 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, 10924125 + 10924126.

It is an arithmetic number, because the mean of its divisors is an integer number (10924126).

Almost surely, 2^21848251 is an apocalyptic number.

21848251 is a deficient number, since it is larger than the sum of its proper divisors (1).

21848251 is an equidigital number, since it uses as much as digits as its factorization.

21848251 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5120, while the sum is 31.

The square root of 21848251 is about 4674.2112703642. The cubic root of 21848251 is about 279.5581935552.

The spelling of 21848251 in words is "twenty-one million, eight hundred forty-eight thousand, two hundred fifty-one".