4397721 has 8 divisors (see below), whose sum is σ = 6172320. Its totient is φ = 2777472.

The previous prime is 4397717. The next prime is 4397737. The reversal of 4397721 is 1277934.

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

It is not a de Polignac number, because 4397721 - 2² = 4397717 is a prime.

4397721 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (4397521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38520 + ... + 38633.

It is an arithmetic number, because the mean of its divisors is an integer number (771540).

Almost surely, 2^4397721 is an apocalyptic number.

It is an amenable number.

4397721 is a deficient number, since it is larger than the sum of its proper divisors (1774599).

4397721 is a wasteful number, since it uses less digits than its factorization.

4397721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77175.

The product of its digits is 10584, while the sum is 33.

The square root of 4397721 is about 2097.0743906691. The cubic root of 4397721 is about 163.8359578224.

The spelling of 4397721 in words is "four million, three hundred ninety-seven thousand, seven hundred twenty-one".