6421428401 has 2 divisors, whose sum is σ = 6421428402. Its totient is φ = 6421428400.

The previous prime is 6421428361. The next prime is 6421428407. The reversal of 6421428401 is 1048241246.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4412147776 + 2009280625 = 66424^2 + 44825^2 .

It is a cyclic number.

It is not a de Polignac number, because 6421428401 - 2²⁶ = 6354319537 is a prime.

It is not a weakly prime, because it can be changed into another prime (6421428407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3210714200 + 3210714201.

It is an arithmetic number, because the mean of its divisors is an integer number (3210714201).

Almost surely, 2^6421428401 is an apocalyptic number.

It is an amenable number.

6421428401 is a deficient number, since it is larger than the sum of its proper divisors (1).

6421428401 is an equidigital number, since it uses as much as digits as its factorization.

6421428401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12288, while the sum is 32.

The square root of 6421428401 is about 80133.8155899243. The cubic root of 6421428401 is about 1858.7053465119.

Adding to 6421428401 its reverse (1048241246), we get a palindrome (7469669647).

The spelling of 6421428401 in words is "six billion, four hundred twenty-one million, four hundred twenty-eight thousand, four hundred one".