6121393638821 has 2 divisors, whose sum is σ = 6121393638822. Its totient is φ = 6121393638820.

The previous prime is 6121393638817. The next prime is 6121393638847. The reversal of 6121393638821 is 1288363931216.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5281309572100 + 840084066721 = 2298110^2 + 916561^2 .

It is a cyclic number.

It is not a de Polignac number, because 6121393638821 - 2² = 6121393638817 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6121393628821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3060696819410 + 3060696819411.

It is an arithmetic number, because the mean of its divisors is an integer number (3060696819411).

Almost surely, 2^{6121393638821} is an apocalyptic number.

It is an amenable number.

6121393638821 is a deficient number, since it is larger than the sum of its proper divisors (1).

6121393638821 is an equidigital number, since it uses as much as digits as its factorization.

6121393638821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2239488, while the sum is 53.

The spelling of 6121393638821 in words is "six trillion, one hundred twenty-one billion, three hundred ninety-three million, six hundred thirty-eight thousand, eight hundred twenty-one".