21270533 has 2 divisors, whose sum is σ = 21270534. Its totient is φ = 21270532.

The previous prime is 21270527. The next prime is 21270539. The reversal of 21270533 is 33507212.

It is a balanced prime because it is at equal distance from previous prime (21270527) and next prime (21270539).

It can be written as a sum of positive squares in only one way, i.e., 16176484 + 5094049 = 4022^2 + 2257^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21270533 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21270499 and 21270508.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21270539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10635266 + 10635267.

It is an arithmetic number, because the mean of its divisors is an integer number (10635267).

Almost surely, 2^21270533 is an apocalyptic number.

It is an amenable number.

21270533 is a deficient number, since it is larger than the sum of its proper divisors (1).

21270533 is an equidigital number, since it uses as much as digits as its factorization.

21270533 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1260, while the sum is 23.

The square root of 21270533 is about 4611.9988074586. The cubic root of 21270533 is about 277.0720965135.

Adding to 21270533 its reverse (33507212), we get a palindrome (54777745).

The spelling of 21270533 in words is "twenty-one million, two hundred seventy thousand, five hundred thirty-three".