21826417 has 2 divisors, whose sum is σ = 21826418. Its totient is φ = 21826416.

The previous prime is 21826397. The next prime is 21826439. The reversal of 21826417 is 71462812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17969121 + 3857296 = 4239^2 + 1964^2 .

It is a cyclic number.

It is not a de Polignac number, because 21826417 - 2¹⁵ = 21793649 is a prime.

It is not a weakly prime, because it can be changed into another prime (21826457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10913208 + 10913209.

It is an arithmetic number, because the mean of its divisors is an integer number (10913209).

Almost surely, 2^21826417 is an apocalyptic number.

It is an amenable number.

21826417 is a deficient number, since it is larger than the sum of its proper divisors (1).

21826417 is an equidigital number, since it uses as much as digits as its factorization.

21826417 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5376, while the sum is 31.

The square root of 21826417 is about 4671.8751053512. The cubic root of 21826417 is about 279.4650372345.

The spelling of 21826417 in words is "twenty-one million, eight hundred twenty-six thousand, four hundred seventeen".