21867941 has 2 divisors, whose sum is σ = 21867942. Its totient is φ = 21867940.

The previous prime is 21867931. The next prime is 21867949. The reversal of 21867941 is 14976812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21669025 + 198916 = 4655^2 + 446^2 .

It is a cyclic number.

It is not a de Polignac number, because 21867941 - 2¹⁰ = 21866917 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21867895 and 21867904.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21867949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10933970 + 10933971.

It is an arithmetic number, because the mean of its divisors is an integer number (10933971).

Almost surely, 2^21867941 is an apocalyptic number.

It is an amenable number.

21867941 is a deficient number, since it is larger than the sum of its proper divisors (1).

21867941 is an equidigital number, since it uses as much as digits as its factorization.

21867941 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24192, while the sum is 38.

The square root of 21867941 is about 4676.3170337350. The cubic root of 21867941 is about 279.6421491401.

The spelling of 21867941 in words is "twenty-one million, eight hundred sixty-seven thousand, nine hundred forty-one".