6506556649 has 4 divisors (see below), whose sum is σ = 6595687636. Its totient is φ = 6417425664.

The previous prime is 6506556599. The next prime is 6506556689. The reversal of 6506556649 is 9466556056.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2075258025 + 4431298624 = 45555^2 + 66568^2 .

It is a cyclic number.

It is not a de Polignac number, because 6506556649 - 2¹⁹ = 6506032361 is a prime.

It is a super-2 number, since 2×6506556649² = 84670558853292218402, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6506556596 and 6506556605.

It is not an unprimeable number, because it can be changed into a prime (6506556689) 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, 44565384 + ... + 44565529.

It is an arithmetic number, because the mean of its divisors is an integer number (1648921909).

Almost surely, 2^6506556649 is an apocalyptic number.

It is an amenable number.

6506556649 is a deficient number, since it is larger than the sum of its proper divisors (89130987).

6506556649 is an equidigital number, since it uses as much as digits as its factorization.

6506556649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89130986.

The product of its (nonzero) digits is 5832000, while the sum is 52.

The square root of 6506556649 is about 80663.2298448308. The cubic root of 6506556649 is about 1866.8828743437.

The spelling of 6506556649 in words is "six billion, five hundred six million, five hundred fifty-six thousand, six hundred forty-nine".