21354433 has 2 divisors, whose sum is σ = 21354434. Its totient is φ = 21354432.

The previous prime is 21354413. The next prime is 21354449. The reversal of 21354433 is 33445312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20539024 + 815409 = 4532^2 + 903^2 .

It is a cyclic number.

It is not a de Polignac number, because 21354433 - 2²¹ = 19257281 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21354398 and 21354407.

It is not a weakly prime, because it can be changed into another prime (21354413) 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, 10677216 + 10677217.

It is an arithmetic number, because the mean of its divisors is an integer number (10677217).

Almost surely, 2^21354433 is an apocalyptic number.

It is an amenable number.

21354433 is a deficient number, since it is larger than the sum of its proper divisors (1).

21354433 is an equidigital number, since it uses as much as digits as its factorization.

21354433 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4320, while the sum is 25.

The square root of 21354433 is about 4621.0856949423. The cubic root of 21354433 is about 277.4359151857.

Adding to 21354433 its reverse (33445312), we get a palindrome (54799745).

The spelling of 21354433 in words is "twenty-one million, three hundred fifty-four thousand, four hundred thirty-three".