21388327 has 2 divisors, whose sum is σ = 21388328. Its totient is φ = 21388326.

The previous prime is 21388313. The next prime is 21388333. The reversal of 21388327 is 72388312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21388327 - 2¹¹ = 21386279 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21388292 and 21388301.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21382327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10694163 + 10694164.

It is an arithmetic number, because the mean of its divisors is an integer number (10694164).

Almost surely, 2^21388327 is an apocalyptic number.

21388327 is a deficient number, since it is larger than the sum of its proper divisors (1).

21388327 is an equidigital number, since it uses as much as digits as its factorization.

21388327 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16128, while the sum is 34.

The square root of 21388327 is about 4624.7515608949. The cubic root of 21388327 is about 277.5826207467.

The spelling of 21388327 in words is "twenty-one million, three hundred eighty-eight thousand, three hundred twenty-seven".