21849941 has 2 divisors, whose sum is σ = 21849942. Its totient is φ = 21849940.

The previous prime is 21849937. The next prime is 21849979. The reversal of 21849941 is 14994812.

It is an a-pointer prime, because the next prime (21849979) can be obtained adding 21849941 to its sum of digits (38).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19140625 + 2709316 = 4375^2 + 1646^2 .

It is a cyclic number.

It is not a de Polignac number, because 21849941 - 2² = 21849937 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21849895 and 21849904.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21849911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10924970 + 10924971.

It is an arithmetic number, because the mean of its divisors is an integer number (10924971).

Almost surely, 2^21849941 is an apocalyptic number.

It is an amenable number.

21849941 is a deficient number, since it is larger than the sum of its proper divisors (1).

21849941 is an equidigital number, since it uses as much as digits as its factorization.

21849941 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 38.

The square root of 21849941 is about 4674.3920460312. The cubic root of 21849941 is about 279.5654014726.

The spelling of 21849941 in words is "twenty-one million, eight hundred forty-nine thousand, nine hundred forty-one".