21043110133221 has 24 divisors (see below), whose sum is σ = 31230420493440. Its totient is φ = 12591964619520.

The previous prime is 21043110133163. The next prime is 21043110133249. The reversal of 21043110133221 is 12233101134012.

It is not a de Polignac number, because 21043110133221 - 2¹⁴ = 21043110116837 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21043110133191 and 21043110133200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21043110133271) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 366870060 + ... + 366927413.

It is an arithmetic number, because the mean of its divisors is an integer number (1301267520560).

Almost surely, 2^{21043110133221} is an apocalyptic number.

It is an amenable number.

21043110133221 is a deficient number, since it is larger than the sum of its proper divisors (10187310360219).

21043110133221 is a wasteful number, since it uses less digits than its factorization.

21043110133221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 733797577 (or 733797566 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

Adding to 21043110133221 its reverse (12233101134012), we get a palindrome (33276211267233).

The spelling of 21043110133221 in words is "twenty-one trillion, forty-three billion, one hundred ten million, one hundred thirty-three thousand, two hundred twenty-one".