6446981 has 2 divisors, whose sum is σ = 6446982. Its totient is φ = 6446980.

The previous prime is 6446971. The next prime is 6446987. The reversal of 6446981 is 1896446.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5428900 + 1018081 = 2330^2 + 1009^2 .

It is a cyclic number.

It is not a de Polignac number, because 6446981 - 2¹⁴ = 6430597 is a prime.

It is a super-2 number, since 2×6446981² = 83127128028722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6446987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3223490 + 3223491.

It is an arithmetic number, because the mean of its divisors is an integer number (3223491).

Almost surely, 2^6446981 is an apocalyptic number.

It is an amenable number.

6446981 is a deficient number, since it is larger than the sum of its proper divisors (1).

6446981 is an equidigital number, since it uses as much as digits as its factorization.

6446981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 41472, while the sum is 38.

The square root of 6446981 is about 2539.0905852293. The cubic root of 6446981 is about 186.1167513814.

The spelling of 6446981 in words is "six million, four hundred forty-six thousand, nine hundred eighty-one".