6418981 has 2 divisors, whose sum is σ = 6418982. Its totient is φ = 6418980.

The previous prime is 6418967. The next prime is 6418991. The reversal of 6418981 is 1898146.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5832225 + 586756 = 2415^2 + 766^2 .

It is a cyclic number.

It is not a de Polignac number, because 6418981 - 2⁵ = 6418949 is a prime.

It is a super-2 number, since 2×6418981² = 82406634156722, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6418981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6418991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3209490 + 3209491.

It is an arithmetic number, because the mean of its divisors is an integer number (3209491).

Almost surely, 2^6418981 is an apocalyptic number.

It is an amenable number.

6418981 is a deficient number, since it is larger than the sum of its proper divisors (1).

6418981 is an equidigital number, since it uses as much as digits as its factorization.

6418981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13824, while the sum is 37.

The square root of 6418981 is about 2533.5708002738. The cubic root of 6418981 is about 185.8469180191.

The spelling of 6418981 in words is "six million, four hundred eighteen thousand, nine hundred eighty-one".