21013334021 has 8 divisors (see below), whose sum is σ = 21477095424. Its totient is φ = 20554233840.

The previous prime is 21013334009. The next prime is 21013334081. The reversal of 21013334021 is 12043331012.

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 21013334021 - 2³⁴ = 3833464837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21013333984 and 21013334002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21013334081) 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, 1156190 + ... + 1174223.

It is an arithmetic number, because the mean of its divisors is an integer number (2684636928).

Almost surely, 2^21013334021 is an apocalyptic number.

It is an amenable number.

21013334021 is a deficient number, since it is larger than the sum of its proper divisors (463761403).

21013334021 is a wasteful number, since it uses less digits than its factorization.

21013334021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2330611.

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 21013334021 its reverse (12043331012), we get a palindrome (33056665033).

The spelling of 21013334021 in words is "twenty-one billion, thirteen million, three hundred thirty-four thousand, twenty-one".