6640847651 has 4 divisors (see below), whose sum is σ = 6641065392. Its totient is φ = 6640629912.

The previous prime is 6640847639. The next prime is 6640847669. The reversal of 6640847651 is 1567480466.

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

It is a cyclic number.

It is not a de Polignac number, because 6640847651 - 2¹⁰ = 6640846627 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6640847596 and 6640847605.

It is not an unprimeable number, because it can be changed into a prime (6640847671) 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 3 ways as a sum of consecutive naturals, for example, 53855 + ... + 127208.

It is an arithmetic number, because the mean of its divisors is an integer number (1660266348).

Almost surely, 2^6640847651 is an apocalyptic number.

6640847651 is a deficient number, since it is larger than the sum of its proper divisors (217741).

6640847651 is a wasteful number, since it uses less digits than its factorization.

6640847651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217740.

The product of its (nonzero) digits is 967680, while the sum is 47.

The square root of 6640847651 is about 81491.3961777561. The cubic root of 6640847651 is about 1879.6392520241.

The spelling of 6640847651 in words is "six billion, six hundred forty million, eight hundred forty-seven thousand, six hundred fifty-one".