7864221 has 8 divisors (see below), whose sum is σ = 10568704. Its totient is φ = 5201280.

The previous prime is 7864201. The next prime is 7864243. The reversal of 7864221 is 1224687.

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

It is not a de Polignac number, because 7864221 - 2⁷ = 7864093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7864201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9940 + ... + 10701.

It is an arithmetic number, because the mean of its divisors is an integer number (1321088).

Almost surely, 2^7864221 is an apocalyptic number.

It is an amenable number.

7864221 is a deficient number, since it is larger than the sum of its proper divisors (2704483).

7864221 is a wasteful number, since it uses less digits than its factorization.

7864221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20771.

The product of its digits is 5376, while the sum is 30.

The square root of 7864221 is about 2804.3218431557. The cubic root of 7864221 is about 198.8620459157.

The spelling of 7864221 in words is "seven million, eight hundred sixty-four thousand, two hundred twenty-one".