21545327 has 2 divisors, whose sum is σ = 21545328. Its totient is φ = 21545326.

The previous prime is 21545311. The next prime is 21545333. The reversal of 21545327 is 72354512.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21545327 - 2⁴ = 21545311 is a prime.

It is a super-2 number, since 2×21545327² = 928402231073858, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21545327.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21545357) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10772663 + 10772664.

It is an arithmetic number, because the mean of its divisors is an integer number (10772664).

Almost surely, 2^21545327 is an apocalyptic number.

21545327 is a deficient number, since it is larger than the sum of its proper divisors (1).

21545327 is an equidigital number, since it uses as much as digits as its factorization.

21545327 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8400, while the sum is 29.

The square root of 21545327 is about 4641.6944104497. The cubic root of 21545327 is about 278.2601596481.

Adding to 21545327 its reverse (72354512), we get a palindrome (93899839).

The spelling of 21545327 in words is "twenty-one million, five hundred forty-five thousand, three hundred twenty-seven".