21655327 has 2 divisors, whose sum is σ = 21655328. Its totient is φ = 21655326.

The previous prime is 21655321. The next prime is 21655367. The reversal of 21655327 is 72355612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21655327 - 2¹¹ = 21653279 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21655321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10827663 + 10827664.

It is an arithmetic number, because the mean of its divisors is an integer number (10827664).

Almost surely, 2^21655327 is an apocalyptic number.

21655327 is a deficient number, since it is larger than the sum of its proper divisors (1).

21655327 is an equidigital number, since it uses as much as digits as its factorization.

21655327 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12600, while the sum is 31.

The square root of 21655327 is about 4653.5284462438. The cubic root of 21655327 is about 278.7329098627.

The spelling of 21655327 in words is "twenty-one million, six hundred fifty-five thousand, three hundred twenty-seven".