6686220840 has 128 divisors (see below), whose sum is σ = 22738665600. Its totient is φ = 1559208960.

The previous prime is 6686220839. The next prime is 6686220857. The reversal of 6686220840 is 480226866.

It is a junction number, because it is equal to n+sod(n) for n = 6686220792 and 6686220801.

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, 83151 + ... + 142430.

It is an arithmetic number, because the mean of its divisors is an integer number (177645825).

Almost surely, 2^6686220840 is an apocalyptic number.

6686220840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6686220840 is an abundant number, since it is smaller than the sum of its proper divisors (16052444760).

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

6686220840 is a wasteful number, since it uses less digits than its factorization.

6686220840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225627 (or 225623 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 42.

The square root of 6686220840 is about 81769.3147825026. The cubic root of 6686220840 is about 1883.9103797507.

The spelling of 6686220840 in words is "six billion, six hundred eighty-six million, two hundred twenty thousand, eight hundred forty".