6607981 has 2 divisors, whose sum is σ = 6607982. Its totient is φ = 6607980.

The previous prime is 6607967. The next prime is 6608003. The reversal of 6607981 is 1897066.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5597956 + 1010025 = 2366^2 + 1005^2 .

It is a cyclic number.

It is not a de Polignac number, because 6607981 - 2⁵ = 6607949 is a prime.

It is a super-2 number, since 2×6607981² = 87330825792722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 6607981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6607961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3303990 + 3303991.

It is an arithmetic number, because the mean of its divisors is an integer number (3303991).

Almost surely, 2^6607981 is an apocalyptic number.

It is an amenable number.

6607981 is a deficient number, since it is larger than the sum of its proper divisors (1).

6607981 is an equidigital number, since it uses as much as digits as its factorization.

6607981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18144, while the sum is 37.

The square root of 6607981 is about 2570.5993464560. The cubic root of 6607981 is about 187.6533240699.

Subtracting from 6607981 its reverse (1897066), we obtain a triangular number (4710915 = T₃₀₆₉).

The spelling of 6607981 in words is "six million, six hundred seven thousand, nine hundred eighty-one".