6679640 has 128 divisors (see below), whose sum is σ = 18662400. Its totient is φ = 2119680.

The previous prime is 6679639. The next prime is 6679661. The reversal of 6679640 is 469766.

6679640 = T₁₉₁ + T₁₉₂ + ... + T₃₆₀.

It is a hoax number, since the sum of its digits (38) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a junction number, because it is equal to n+sod(n) for n = 6679594 and 6679603.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 142097 + ... + 142143.

It is an arithmetic number, because the mean of its divisors is an integer number (145800).

Almost surely, 2^6679640 is an apocalyptic number.

It is a pronic number, being equal to 2584×2585.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6679640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9331200).

6679640 is an abundant number, since it is smaller than the sum of its proper divisors (11982760).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6679640 is a wasteful number, since it uses less digits than its factorization.

6679640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105 (or 101 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 38.

The square root of 6679640 is about 2584.4999516347. The cubic root of 6679640 is about 188.3292104109.

The spelling of 6679640 in words is "six million, six hundred seventy-nine thousand, six hundred forty".