21033011021 has 8 divisors (see below), whose sum is σ = 22959453888. Its totient is φ = 19108960000.

The previous prime is 21033011017. The next prime is 21033011071. The reversal of 21033011021 is 12011033012.

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 21033011021 - 2² = 21033011017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21033010987 and 21033011005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21033011071) 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, 579545 + ... + 614766.

It is an arithmetic number, because the mean of its divisors is an integer number (2869931736).

Almost surely, 2^21033011021 is an apocalyptic number.

It is an amenable number.

21033011021 is a deficient number, since it is larger than the sum of its proper divisors (1926442867).

21033011021 is a wasteful number, since it uses less digits than its factorization.

21033011021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1195923.

The product of its (nonzero) digits is 36, while the sum is 14.

Adding to 21033011021 its reverse (12011033012), we get a palindrome (33044044033).

The spelling of 21033011021 in words is "twenty-one billion, thirty-three million, eleven thousand, twenty-one".