4557721 has 4 divisors (see below), whose sum is σ = 5208832. Its totient is φ = 3906612.

The previous prime is 4557719. The next prime is 4557743. The reversal of 4557721 is 1277554.

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 a cyclic number.

It is not a de Polignac number, because 4557721 - 2¹ = 4557719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4557781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 325545 + ... + 325558.

It is an arithmetic number, because the mean of its divisors is an integer number (1302208).

Almost surely, 2^4557721 is an apocalyptic number.

It is an amenable number.

4557721 is a deficient number, since it is larger than the sum of its proper divisors (651111).

4557721 is an equidigital number, since it uses as much as digits as its factorization.

4557721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 651110.

The product of its digits is 9800, while the sum is 31.

The square root of 4557721 is about 2134.8819639502. The cubic root of 4557721 is about 165.7992565408.

The spelling of 4557721 in words is "four million, five hundred fifty-seven thousand, seven hundred twenty-one".