21707927 has 2 divisors, whose sum is σ = 21707928. Its totient is φ = 21707926.

The previous prime is 21707909. The next prime is 21707941. The reversal of 21707927 is 72970712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21707927 - 2¹² = 21703831 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21707947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10853963 + 10853964.

It is an arithmetic number, because the mean of its divisors is an integer number (10853964).

Almost surely, 2^21707927 is an apocalyptic number.

21707927 is a deficient number, since it is larger than the sum of its proper divisors (1).

21707927 is an equidigital number, since it uses as much as digits as its factorization.

21707927 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12348, while the sum is 35.

The square root of 21707927 is about 4659.1766440005. The cubic root of 21707927 is about 278.9584047478.

The spelling of 21707927 in words is "twenty-one million, seven hundred seven thousand, nine hundred twenty-seven".