6440666361 has 8 divisors (see below), whose sum is σ = 8864573184. Its totient is φ = 4155268560.

The previous prime is 6440666357. The next prime is 6440666389. The reversal of 6440666361 is 1636660446.

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

It is not a de Polignac number, because 6440666361 - 2² = 6440666357 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6440666161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34627146 + ... + 34627331.

It is an arithmetic number, because the mean of its divisors is an integer number (1108071648).

Almost surely, 2^6440666361 is an apocalyptic number.

It is an amenable number.

6440666361 is a deficient number, since it is larger than the sum of its proper divisors (2423906823).

6440666361 is a wasteful number, since it uses less digits than its factorization.

6440666361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69254511.

The product of its (nonzero) digits is 373248, while the sum is 42.

The square root of 6440666361 is about 80253.7622856399. The cubic root of 6440666361 is about 1860.5596613339.

The spelling of 6440666361 in words is "six billion, four hundred forty million, six hundred sixty-six thousand, three hundred sixty-one".