21220034240321 has 16 divisors (see below), whose sum is σ = 24308678983680. Its totient is φ = 18145695597840.

The previous prime is 21220034240311. The next prime is 21220034240333. The reversal of 21220034240321 is 12304243002212.

It is a cyclic number.

It is not a de Polignac number, because 21220034240321 - 2¹⁸ = 21220033978177 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21220034240311) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 86788640 + ... + 87032798.

It is an arithmetic number, because the mean of its divisors is an integer number (1519292436480).

Almost surely, 2^{21220034240321} is an apocalyptic number.

It is an amenable number.

21220034240321 is a deficient number, since it is larger than the sum of its proper divisors (3088644743359).

21220034240321 is a wasteful number, since it uses less digits than its factorization.

21220034240321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273404.

The product of its (nonzero) digits is 4608, while the sum is 26.

Adding to 21220034240321 its reverse (12304243002212), we get a palindrome (33524277242533).

The spelling of 21220034240321 in words is "twenty-one trillion, two hundred twenty billion, thirty-four million, two hundred forty thousand, three hundred twenty-one".