6500660981 has 2 divisors, whose sum is σ = 6500660982. Its totient is φ = 6500660980.

The previous prime is 6500660951. The next prime is 6500661019. The reversal of 6500660981 is 1890660056.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4747899025 + 1752761956 = 68905^2 + 41866^2 .

It is a cyclic number.

It is not a de Polignac number, because 6500660981 - 2¹⁴ = 6500644597 is a prime.

It is a super-2 number, since 2×6500660981² = 84517186379791764722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6500660951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3250330490 + 3250330491.

It is an arithmetic number, because the mean of its divisors is an integer number (3250330491).

Almost surely, 2^6500660981 is an apocalyptic number.

It is an amenable number.

6500660981 is a deficient number, since it is larger than the sum of its proper divisors (1).

6500660981 is an equidigital number, since it uses as much as digits as its factorization.

6500660981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 77760, while the sum is 41.

The square root of 6500660981 is about 80626.6766089239. The cubic root of 6500660981 is about 1866.3188357249.

The spelling of 6500660981 in words is "six billion, five hundred million, six hundred sixty thousand, nine hundred eighty-one".