21445727 has 2 divisors, whose sum is σ = 21445728. Its totient is φ = 21445726.

The previous prime is 21445717. The next prime is 21445751. The reversal of 21445727 is 72754412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21445727 - 2²⁴ = 4668511 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21445693 and 21445702.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21445717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10722863 + 10722864.

It is an arithmetic number, because the mean of its divisors is an integer number (10722864).

Almost surely, 2^21445727 is an apocalyptic number.

21445727 is a deficient number, since it is larger than the sum of its proper divisors (1).

21445727 is an equidigital number, since it uses as much as digits as its factorization.

21445727 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15680, while the sum is 32.

The square root of 21445727 is about 4630.9531416329. The cubic root of 21445727 is about 277.8307157358.

The spelling of 21445727 in words is "twenty-one million, four hundred forty-five thousand, seven hundred twenty-seven".