21426827 has 2 divisors, whose sum is σ = 21426828. Its totient is φ = 21426826.

The previous prime is 21426809. The next prime is 21426841. The reversal of 21426827 is 72862412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21426827 - 2⁶ = 21426763 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21426793 and 21426802.

It is not a weakly prime, because it can be changed into another prime (21420827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10713413 + 10713414.

It is an arithmetic number, because the mean of its divisors is an integer number (10713414).

Almost surely, 2^21426827 is an apocalyptic number.

21426827 is a deficient number, since it is larger than the sum of its proper divisors (1).

21426827 is an equidigital number, since it uses as much as digits as its factorization.

21426827 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10752, while the sum is 32.

The square root of 21426827 is about 4628.9120752073. The cubic root of 21426827 is about 277.7490748594.

The spelling of 21426827 in words is "twenty-one million, four hundred twenty-six thousand, eight hundred twenty-seven".