6644869691 has 4 divisors (see below), whose sum is σ = 6678600192. Its totient is φ = 6611139192.

The previous prime is 6644869687. The next prime is 6644869703. The reversal of 6644869691 is 1969684466.

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 6644869691 - 2² = 6644869687 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6644869691.

It is not an unprimeable number, because it can be changed into a prime (6644869291) 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, 16864955 + ... + 16865348.

It is an arithmetic number, because the mean of its divisors is an integer number (1669650048).

Almost surely, 2^6644869691 is an apocalyptic number.

6644869691 is a deficient number, since it is larger than the sum of its proper divisors (33730501).

6644869691 is a wasteful number, since it uses less digits than its factorization.

6644869691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33730500.

The product of its digits is 13436928, while the sum is 59.

The square root of 6644869691 is about 81516.0701395743. The cubic root of 6644869691 is about 1880.0186442809.

The spelling of 6644869691 in words is "six billion, six hundred forty-four million, eight hundred sixty-nine thousand, six hundred ninety-one".