6642281 has 2 divisors, whose sum is σ = 6642282. Its totient is φ = 6642280.

The previous prime is 6642211. The next prime is 6642283. The reversal of 6642281 is 1822466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3936256 + 2706025 = 1984^2 + 1645^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6642281 is a prime.

It is a super-2 number, since 2×6642281² = 88239793765922, which contains 22 as substring.

Together with 6642283, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p₄₅₃₈₅₄ and since 6642281 and 453854 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (6642283) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3321140 + 3321141.

It is an arithmetic number, because the mean of its divisors is an integer number (3321141).

Almost surely, 2^6642281 is an apocalyptic number.

It is an amenable number.

6642281 is a deficient number, since it is larger than the sum of its proper divisors (1).

6642281 is an equidigital number, since it uses as much as digits as its factorization.

6642281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 29.

The square root of 6642281 is about 2577.2623071779. The cubic root of 6642281 is about 187.9774474984.

The spelling of 6642281 in words is "six million, six hundred forty-two thousand, two hundred eighty-one".