21245459 has 2 divisors, whose sum is σ = 21245460. Its totient is φ = 21245458.

The previous prime is 21245417. The next prime is 21245467. The reversal of 21245459 is 95454212.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21245459 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21245479) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10622729 + 10622730.

It is an arithmetic number, because the mean of its divisors is an integer number (10622730).

Almost surely, 2^21245459 is an apocalyptic number.

21245459 is a deficient number, since it is larger than the sum of its proper divisors (1).

21245459 is an equidigital number, since it uses as much as digits as its factorization.

21245459 is an evil number, because the sum of its binary digits is even.

The product of its digits is 14400, while the sum is 32.

The square root of 21245459 is about 4609.2796617259. The cubic root of 21245459 is about 276.9631815591.

The spelling of 21245459 in words is "twenty-one million, two hundred forty-five thousand, four hundred fifty-nine".