6421279 has 2 divisors, whose sum is σ = 6421280. Its totient is φ = 6421278.

The previous prime is 6421271. The next prime is 6421339. The reversal of 6421279 is 9721246.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6421279 - 2³ = 6421271 is a prime.

6421279 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 6421279.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6421271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3210639 + 3210640.

It is an arithmetic number, because the mean of its divisors is an integer number (3210640).

Almost surely, 2^6421279 is an apocalyptic number.

6421279 is a deficient number, since it is larger than the sum of its proper divisors (1).

6421279 is an equidigital number, since it uses as much as digits as its factorization.

6421279 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6048, while the sum is 31.

The square root of 6421279 is about 2534.0242698127. The cubic root of 6421279 is about 185.8690931516.

The spelling of 6421279 in words is "six million, four hundred twenty-one thousand, two hundred seventy-nine".