21946259 has 2 divisors, whose sum is σ = 21946260. Its totient is φ = 21946258.

The previous prime is 21946247. The next prime is 21946271. The reversal of 21946259 is 95264912.

It is a balanced prime because it is at equal distance from previous prime (21946247) and next prime (21946271).

It is a cyclic number.

It is not a de Polignac number, because 21946259 - 2⁸ = 21946003 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21946219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10973129 + 10973130.

It is an arithmetic number, because the mean of its divisors is an integer number (10973130).

Almost surely, 2^21946259 is an apocalyptic number.

21946259 is a deficient number, since it is larger than the sum of its proper divisors (1).

21946259 is an equidigital number, since it uses as much as digits as its factorization.

21946259 is an evil number, because the sum of its binary digits is even.

The product of its digits is 38880, while the sum is 38.

The square root of 21946259 is about 4684.6834471499. The cubic root of 21946259 is about 279.9755888582.

The spelling of 21946259 in words is "twenty-one million, nine hundred forty-six thousand, two hundred fifty-nine".