21533532011 has 4 divisors (see below), whose sum is σ = 21538662024. Its totient is φ = 21528402000.

The previous prime is 21533531989. The next prime is 21533532037. The reversal of 21533532011 is 11023533512.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21533532011 - 2¹⁰ = 21533530987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21533532211) 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, 2558705 + ... + 2567106.

It is an arithmetic number, because the mean of its divisors is an integer number (5384665506).

Almost surely, 2^21533532011 is an apocalyptic number.

21533532011 is a deficient number, since it is larger than the sum of its proper divisors (5130013).

21533532011 is an equidigital number, since it uses as much as digits as its factorization.

21533532011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5130012.

The product of its (nonzero) digits is 2700, while the sum is 26.

The spelling of 21533532011 in words is "twenty-one billion, five hundred thirty-three million, five hundred thirty-two thousand, eleven".