21266299 has 2 divisors, whose sum is σ = 21266300. Its totient is φ = 21266298.

The previous prime is 21266293. The next prime is 21266317. The reversal of 21266299 is 99266212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21266299 - 2³ = 21266291 is a prime.

It is not a weakly prime, because it can be changed into another prime (21266291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10633149 + 10633150.

It is an arithmetic number, because the mean of its divisors is an integer number (10633150).

Almost surely, 2^21266299 is an apocalyptic number.

21266299 is a deficient number, since it is larger than the sum of its proper divisors (1).

21266299 is an equidigital number, since it uses as much as digits as its factorization.

21266299 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23328, while the sum is 37.

The square root of 21266299 is about 4611.5397645472. The cubic root of 21266299 is about 277.0537111240.

The spelling of 21266299 in words is "twenty-one million, two hundred sixty-six thousand, two hundred ninety-nine".