21402530533 has 2 divisors, whose sum is σ = 21402530534. Its totient is φ = 21402530532.

The previous prime is 21402530531. The next prime is 21402530537. The reversal of 21402530533 is 33503520412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13548494404 + 7854036129 = 116398^2 + 88623^2 .

It is a cyclic number.

It is not a de Polignac number, because 21402530533 - 2¹ = 21402530531 is a prime.

Together with 21402530531, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21402530531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10701265266 + 10701265267.

It is an arithmetic number, because the mean of its divisors is an integer number (10701265267).

Almost surely, 2^21402530533 is an apocalyptic number.

It is an amenable number.

21402530533 is a deficient number, since it is larger than the sum of its proper divisors (1).

21402530533 is an equidigital number, since it uses as much as digits as its factorization.

21402530533 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10800, while the sum is 28.

The spelling of 21402530533 in words is "twenty-one billion, four hundred two million, five hundred thirty thousand, five hundred thirty-three".