21433427 has 2 divisors, whose sum is σ = 21433428. Its totient is φ = 21433426.

The previous prime is 21433421. The next prime is 21433439. The reversal of 21433427 is 72433412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21433427 - 2¹⁰ = 21432403 is a prime.

It is a Chen prime.

It is equal to p_1355615 and since 21433427 and 1355615 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 21433396 and 21433405.

It is not a weakly prime, because it can be changed into another prime (21433421) 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, 10716713 + 10716714.

It is an arithmetic number, because the mean of its divisors is an integer number (10716714).

Almost surely, 2^21433427 is an apocalyptic number.

21433427 is a deficient number, since it is larger than the sum of its proper divisors (1).

21433427 is an equidigital number, since it uses as much as digits as its factorization.

21433427 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4032, while the sum is 26.

The square root of 21433427 is about 4629.6249308124. The cubic root of 21433427 is about 277.7775898251. Note that the first 3 decimals are identical.

Adding to 21433427 its reverse (72433412), we get a palindrome (93866839).

The spelling of 21433427 in words is "twenty-one million, four hundred thirty-three thousand, four hundred twenty-seven".