21133541021 has 8 divisors (see below), whose sum is σ = 21541572864. Its totient is φ = 20725853200.

The previous prime is 21133541017. The next prime is 21133541047. The reversal of 21133541021 is 12014533112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21133541021 - 2² = 21133541017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21130541021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39800 + ... + 209406.

It is an arithmetic number, because the mean of its divisors is an integer number (2692696608).

Almost surely, 2^21133541021 is an apocalyptic number.

It is an amenable number.

21133541021 is a deficient number, since it is larger than the sum of its proper divisors (408031843).

21133541021 is a wasteful number, since it uses less digits than its factorization.

21133541021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172011.

The product of its (nonzero) digits is 720, while the sum is 23.

The spelling of 21133541021 in words is "twenty-one billion, one hundred thirty-three million, five hundred forty-one thousand, twenty-one".