6499188536681 has 4 divisors (see below), whose sum is σ = 6514267860864. Its totient is φ = 6484109212500.

The previous prime is 6499188536609. The next prime is 6499188536683. The reversal of 6499188536681 is 1866358819946.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6499188536681 - 2¹⁰ = 6499188535657 is a prime.

It is a super-2 number, since 2×6499188536681² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6499188536599 and 6499188536608.

It is not an unprimeable number, because it can be changed into a prime (6499188536683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7539661445 + ... + 7539662306.

It is an arithmetic number, because the mean of its divisors is an integer number (1628566965216).

Almost surely, 2^{6499188536681} is an apocalyptic number.

It is an amenable number.

6499188536681 is a deficient number, since it is larger than the sum of its proper divisors (15079324183).

6499188536681 is a wasteful number, since it uses less digits than its factorization.

6499188536681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15079324182.

The product of its digits is 537477120, while the sum is 74.

The spelling of 6499188536681 in words is "six trillion, four hundred ninety-nine billion, one hundred eighty-eight million, five hundred thirty-six thousand, six hundred eighty-one".