21450827 has 2 divisors, whose sum is σ = 21450828. Its totient is φ = 21450826.

The previous prime is 21450811. The next prime is 21450839. The reversal of 21450827 is 72805412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21450827 - 2⁴ = 21450811 is a prime.

It is equal to p_1356653 and since 21450827 and 1356653 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21450827.

It is not a weakly prime, because it can be changed into another prime (21450887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10725413 + 10725414.

It is an arithmetic number, because the mean of its divisors is an integer number (10725414).

Almost surely, 2^21450827 is an apocalyptic number.

21450827 is a deficient number, since it is larger than the sum of its proper divisors (1).

21450827 is an equidigital number, since it uses as much as digits as its factorization.

21450827 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4480, while the sum is 29.

The square root of 21450827 is about 4631.5037514829. The cubic root of 21450827 is about 277.8527375951.

The spelling of 21450827 in words is "twenty-one million, four hundred fifty thousand, eight hundred twenty-seven".