21342523521 has 32 divisors (see below), whose sum is σ = 31196689920. Its totient is φ = 12871241600.

The previous prime is 21342523493. The next prime is 21342523591. The reversal of 21342523521 is 12532524312.

It is a cyclic number.

It is not a de Polignac number, because 21342523521 - 2¹³ = 21342515329 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21342523591) 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 in 31 ways as a sum of consecutive naturals, for example, 10783510 + ... + 10785488.

It is an arithmetic number, because the mean of its divisors is an integer number (974896560).

Almost surely, 2^21342523521 is an apocalyptic number.

It is an amenable number.

21342523521 is a deficient number, since it is larger than the sum of its proper divisors (9854166399).

21342523521 is a wasteful number, since it uses less digits than its factorization.

21342523521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3437.

The product of its digits is 14400, while the sum is 30.

The spelling of 21342523521 in words is "twenty-one billion, three hundred forty-two million, five hundred twenty-three thousand, five hundred twenty-one".