6440872 has 8 divisors (see below), whose sum is σ = 12076650. Its totient is φ = 3220432.

The previous prime is 6440831. The next prime is 6440873. The reversal of 6440872 is 2780446.

It can be written as a sum of positive squares in only one way, i.e., 4519876 + 1920996 = 2126^2 + 1386^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (6440873) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 402547 + ... + 402562.

Almost surely, 2^6440872 is an apocalyptic number.

It is an amenable number.

6440872 is a deficient number, since it is larger than the sum of its proper divisors (5635778).

6440872 is a wasteful number, since it uses less digits than its factorization.

6440872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 805115 (or 805111 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 31.

The square root of 6440872 is about 2537.8873103430. The cubic root of 6440872 is about 186.0579462575.

The spelling of 6440872 in words is "six million, four hundred forty thousand, eight hundred seventy-two".