21435529 has 2 divisors, whose sum is σ = 21435530. Its totient is φ = 21435528.

The previous prime is 21435527. The next prime is 21435551. The reversal of 21435529 is 92553412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12145225 + 9290304 = 3485^2 + 3048^2 .

It is a cyclic number.

It is not a de Polignac number, because 21435529 - 2¹ = 21435527 is a prime.

Together with 21435527, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21435529.

It is not a weakly prime, because it can be changed into another prime (21435527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10717764 + 10717765.

It is an arithmetic number, because the mean of its divisors is an integer number (10717765).

Almost surely, 2^21435529 is an apocalyptic number.

It is an amenable number.

21435529 is a deficient number, since it is larger than the sum of its proper divisors (1).

21435529 is an equidigital number, since it uses as much as digits as its factorization.

21435529 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10800, while the sum is 31.

The square root of 21435529 is about 4629.8519414772. The cubic root of 21435529 is about 277.7866701805.

The spelling of 21435529 in words is "twenty-one million, four hundred thirty-five thousand, five hundred twenty-nine".