2121640206443 has 2 divisors, whose sum is σ = 2121640206444. Its totient is φ = 2121640206442.

The previous prime is 2121640206409. The next prime is 2121640206457. The reversal of 2121640206443 is 3446020461212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2121640206443 - 2³⁰ = 2120566464619 is a prime.

It is not a weakly prime, because it can be changed into another prime (2121640206473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060820103221 + 1060820103222.

It is an arithmetic number, because the mean of its divisors is an integer number (1060820103222).

Almost surely, 2^{2121640206443} is an apocalyptic number.

2121640206443 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121640206443 is an equidigital number, since it uses as much as digits as its factorization.

2121640206443 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 55296, while the sum is 35.

Adding to 2121640206443 its reverse (3446020461212), we get a palindrome (5567660667655).

The spelling of 2121640206443 in words is "two trillion, one hundred twenty-one billion, six hundred forty million, two hundred six thousand, four hundred forty-three".