6456639 has 16 divisors (see below), whose sum is σ = 10080000. Its totient is φ = 3599040.

The previous prime is 6456623. The next prime is 6456641. The reversal of 6456639 is 9366546.

It is a happy number.

6456639 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 6456639 - 2⁴ = 6456623 is a prime.

It is a d-powerful number, because it can be written as 6³ + 4¹⁰ + 5³ + 6⁶ + 6⁶ + 3¹⁴ + 9⁶ .

It is a junction number, because it is equal to n+sod(n) for n = 6456597 and 6456606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6456679) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2889 + ... + 4610.

It is an arithmetic number, because the mean of its divisors is an integer number (630000).

Almost surely, 2^6456639 is an apocalyptic number.

6456639 is a deficient number, since it is larger than the sum of its proper divisors (3623361).

6456639 is a wasteful number, since it uses less digits than its factorization.

6456639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7550.

The product of its digits is 116640, while the sum is 39.

The square root of 6456639 is about 2540.9917355238. The cubic root of 6456639 is about 186.2096433739.

The spelling of 6456639 in words is "six million, four hundred fifty-six thousand, six hundred thirty-nine".