21617411 has 2 divisors, whose sum is σ = 21617412. Its totient is φ = 21617410.

The previous prime is 21617381. The next prime is 21617413. The reversal of 21617411 is 11471612.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21617411 - 2¹⁸ = 21355267 is a prime.

Together with 21617413, 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 (21617413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10808705 + 10808706.

It is an arithmetic number, because the mean of its divisors is an integer number (10808706).

Almost surely, 2^21617411 is an apocalyptic number.

21617411 is a deficient number, since it is larger than the sum of its proper divisors (1).

21617411 is an equidigital number, since it uses as much as digits as its factorization.

21617411 is an evil number, because the sum of its binary digits is even.

The product of its digits is 336, while the sum is 23.

The square root of 21617411 is about 4649.4527634981. The cubic root of 21617411 is about 278.5701383491.

The spelling of 21617411 in words is "twenty-one million, six hundred seventeen thousand, four hundred eleven".