20121240342321 has 12 divisors (see below), whose sum is σ = 29064308157300. Its totient is φ = 13414024383840.

The previous prime is 20121240342293. The next prime is 20121240342347. The reversal of 20121240342321 is 12324304212102.

20121240342321 is a `hidden beast` number, since 2 + 0 + 1 + 21 + 2 + 403 + 4 + 232 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 3313987230096 + 16807253112225 = 1820436^2 + 4099665^2 .

It is not a de Polignac number, because 20121240342321 - 2¹¹ = 20121240340273 is a prime.

It is a super-2 number, since 2×20121240342321² (a number of 27 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20121240342121) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10378146 + ... + 12163403.

It is an arithmetic number, because the mean of its divisors is an integer number (2422025679775).

Almost surely, 2^{20121240342321} is an apocalyptic number.

It is an amenable number.

20121240342321 is a deficient number, since it is larger than the sum of its proper divisors (8943067814979).

20121240342321 is a wasteful number, since it uses less digits than its factorization.

20121240342321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22640736 (or 22640733 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

Adding to 20121240342321 its reverse (12324304212102), we get a palindrome (32445544554423).

The spelling of 20121240342321 in words is "twenty trillion, one hundred twenty-one billion, two hundred forty million, three hundred forty-two thousand, three hundred twenty-one".