6645380871 has 8 divisors (see below), whose sum is σ = 8895809664. Its totient is φ = 4412603000.

The previous prime is 6645380849. The next prime is 6645380879. The reversal of 6645380871 is 1780835466.

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 6645380871 - 2⁵ = 6645380839 is a prime.

It is a super-2 number, since 2×6645380871² = 88322173841305437282, 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 6645380871.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6645380879) 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, 4411851 + ... + 4413356.

It is an arithmetic number, because the mean of its divisors is an integer number (1111976208).

Almost surely, 2^6645380871 is an apocalyptic number.

6645380871 is a deficient number, since it is larger than the sum of its proper divisors (2250428793).

6645380871 is a wasteful number, since it uses less digits than its factorization.

6645380871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8825461.

The product of its (nonzero) digits is 967680, while the sum is 48.

The square root of 6645380871 is about 81519.2055346469. The cubic root of 6645380871 is about 1880.0668520629.

The spelling of 6645380871 in words is "six billion, six hundred forty-five million, three hundred eighty thousand, eight hundred seventy-one".