21268579 has 2 divisors, whose sum is σ = 21268580. Its totient is φ = 21268578.

The previous prime is 21268567. The next prime is 21268591. The reversal of 21268579 is 97586212.

It is a balanced prime because it is at equal distance from previous prime (21268567) and next prime (21268591).

It is a cyclic number.

It is not a de Polignac number, because 21268579 - 2¹⁷ = 21137507 is a prime.

It is not a weakly prime, because it can be changed into another prime (21268679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10634289 + 10634290.

It is an arithmetic number, because the mean of its divisors is an integer number (10634290).

Almost surely, 2^21268579 is an apocalyptic number.

21268579 is a deficient number, since it is larger than the sum of its proper divisors (1).

21268579 is an equidigital number, since it uses as much as digits as its factorization.

21268579 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 60480, while the sum is 40.

The square root of 21268579 is about 4611.7869638569. The cubic root of 21268579 is about 277.0636119204.

The spelling of 21268579 in words is "twenty-one million, two hundred sixty-eight thousand, five hundred seventy-nine".