8327721 has 4 divisors (see below), whose sum is σ = 11103632. Its totient is φ = 5551812.

The previous prime is 8327717. The next prime is 8327743. The reversal of 8327721 is 1277238.

8327721 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 8327721 - 2² = 8327717 is a prime.

It is a Duffinian number.

8327721 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (8327021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1387951 + ... + 1387956.

It is an arithmetic number, because the mean of its divisors is an integer number (2775908).

Almost surely, 2^8327721 is an apocalyptic number.

It is an amenable number.

8327721 is a deficient number, since it is larger than the sum of its proper divisors (2775911).

8327721 is a wasteful number, since it uses less digits than its factorization.

8327721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2775910.

The product of its digits is 4704, while the sum is 30.

The square root of 8327721 is about 2885.7790975749. The cubic root of 8327721 is about 202.6945425044.

The spelling of 8327721 in words is "eight million, three hundred twenty-seven thousand, seven hundred twenty-one".