21200132521 has 4 divisors (see below), whose sum is σ = 21352651600. Its totient is φ = 21047613444.

The previous prime is 21200132497. The next prime is 21200132549. The reversal of 21200132521 is 12523100212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21200132521 - 2¹⁹ = 21199608233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21200132621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 76259331 + ... + 76259608.

It is an arithmetic number, because the mean of its divisors is an integer number (5338162900).

Almost surely, 2^21200132521 is an apocalyptic number.

It is an amenable number.

21200132521 is a deficient number, since it is larger than the sum of its proper divisors (152519079).

21200132521 is a wasteful number, since it uses less digits than its factorization.

21200132521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152519078.

The product of its (nonzero) digits is 240, while the sum is 19.

Adding to 21200132521 its reverse (12523100212), we get a palindrome (33723232733).

The spelling of 21200132521 in words is "twenty-one billion, two hundred million, one hundred thirty-two thousand, five hundred twenty-one".