21799241 has 2 divisors, whose sum is σ = 21799242. Its totient is φ = 21799240.

The previous prime is 21799199. The next prime is 21799243. The reversal of 21799241 is 14299712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11424400 + 10374841 = 3380^2 + 3221^2 .

It is a cyclic number.

It is not a de Polignac number, because 21799241 - 2⁶ = 21799177 is a prime.

Together with 21799243, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21799243) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10899620 + 10899621.

It is an arithmetic number, because the mean of its divisors is an integer number (10899621).

Almost surely, 2^21799241 is an apocalyptic number.

It is an amenable number.

21799241 is a deficient number, since it is larger than the sum of its proper divisors (1).

21799241 is an equidigital number, since it uses as much as digits as its factorization.

21799241 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9072, while the sum is 35.

The square root of 21799241 is about 4668.9657312942. The cubic root of 21799241 is about 279.3490020634.

The spelling of 21799241 in words is "twenty-one million, seven hundred ninety-nine thousand, two hundred forty-one".