6721818 has 8 divisors (see below), whose sum is σ = 13443648. Its totient is φ = 2240604.

The previous prime is 6721789. The next prime is 6721843. The reversal of 6721818 is 8181276.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

6721818 is an admirable number.

It is an alternating number because its digits alternate between even and odd.

6721818 is a modest number, since divided by 1818 gives 672 as remainder.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 560146 + ... + 560157.

It is an arithmetic number, because the mean of its divisors is an integer number (1680456).

Almost surely, 2^6721818 is an apocalyptic number.

6721818 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

6721818 is a wasteful number, since it uses less digits than its factorization.

6721818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1120308.

The product of its digits is 5376, while the sum is 33.

The square root of 6721818 is about 2592.6469100130. The cubic root of 6721818 is about 188.7247750744.

The spelling of 6721818 in words is "six million, seven hundred twenty-one thousand, eight hundred eighteen".