6506981749 has 8 divisors (see below), whose sum is σ = 6732495000. Its totient is φ = 6281544192.

The previous prime is 6506981743. The next prime is 6506981753. The reversal of 6506981749 is 9471896056.

It can be written as a sum of positive squares in 4 ways, for example, as 1179441649 + 5327540100 = 34343^2 + 72990^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6506981749 - 2⁹ = 6506981237 is a prime.

It is a super-2 number, since 2×6506981749² = 84681622963638198002, 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 6506981749.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6506981743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 198477 + ... + 228925.

It is an arithmetic number, because the mean of its divisors is an integer number (841561875).

Almost surely, 2^6506981749 is an apocalyptic number.

It is an amenable number.

6506981749 is a deficient number, since it is larger than the sum of its proper divisors (225513251).

6506981749 is a wasteful number, since it uses less digits than its factorization.

6506981749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37847.

The product of its (nonzero) digits is 3265920, while the sum is 55.

The square root of 6506981749 is about 80665.8648314143. The cubic root of 6506981749 is about 1866.9235304936.

The spelling of 6506981749 in words is "six billion, five hundred six million, nine hundred eighty-one thousand, seven hundred forty-nine".