6421320257377 has 2 divisors, whose sum is σ = 6421320257378. Its totient is φ = 6421320257376.

The previous prime is 6421320257321. The next prime is 6421320257393. The reversal of 6421320257377 is 7737520231246.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6075022139536 + 346298117841 = 2464756^2 + 588471^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6421320257377 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6421320257377.

It is not a weakly prime, because it can be changed into another prime (6421320257777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3210660128688 + 3210660128689.

It is an arithmetic number, because the mean of its divisors is an integer number (3210660128689).

Almost surely, 2^{6421320257377} is an apocalyptic number.

It is an amenable number.

6421320257377 is a deficient number, since it is larger than the sum of its proper divisors (1).

6421320257377 is an equidigital number, since it uses as much as digits as its factorization.

6421320257377 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2963520, while the sum is 49.

The spelling of 6421320257377 in words is "six trillion, four hundred twenty-one billion, three hundred twenty million, two hundred fifty-seven thousand, three hundred seventy-seven".