2121343220431 has 4 divisors (see below), whose sum is σ = 2121349704664. Its totient is φ = 2121336736200.

The previous prime is 2121343220419. The next prime is 2121343220443. The reversal of 2121343220431 is 1340223431212.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (2121343220419) and next prime (2121343220443).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2121343220431 is a prime.

It is a super-2 number, since 2×2121343220431² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2121343220431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121343220411) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2723760 + ... + 3414901.

It is an arithmetic number, because the mean of its divisors is an integer number (530337426166).

Almost surely, 2^{2121343220431} is an apocalyptic number.

2121343220431 is a deficient number, since it is larger than the sum of its proper divisors (6484233).

2121343220431 is an equidigital number, since it uses as much as digits as its factorization.

2121343220431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6484232.

The product of its (nonzero) digits is 6912, while the sum is 28.

Adding to 2121343220431 its reverse (1340223431212), we get a palindrome (3461566651643).

The spelling of 2121343220431 in words is "two trillion, one hundred twenty-one billion, three hundred forty-three million, two hundred twenty thousand, four hundred thirty-one".