6721228 has 12 divisors (see below), whose sum is σ = 11808720. Its totient is φ = 3347312.

The previous prime is 6721219. The next prime is 6721237. The reversal of 6721228 is 8221276.

It is an interprime number because it is at equal distance from previous prime (6721219) and next prime (6721237).

It is a junction number, because it is equal to n+sod(n) for n = 6721196 and 6721205.

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, 2143 + ... + 4246.

It is an arithmetic number, because the mean of its divisors is an integer number (984060).

Almost surely, 2^6721228 is an apocalyptic number.

It is an amenable number.

6721228 is a deficient number, since it is larger than the sum of its proper divisors (5087492).

6721228 is a wasteful number, since it uses less digits than its factorization.

6721228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6656 (or 6654 counting only the distinct ones).

The product of its digits is 2688, while the sum is 28.

The square root of 6721228 is about 2592.5331241857. The cubic root of 6721228 is about 188.7192532114.

The spelling of 6721228 in words is "six million, seven hundred twenty-one thousand, two hundred twenty-eight".