4030721 has 4 divisors (see below), whose sum is σ = 4076100. Its totient is φ = 3985344.

The previous prime is 4030709. The next prime is 4030757. The reversal of 4030721 is 1270304.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2070721 + 1960000 = 1439^2 + 1400^2 .

It is a cyclic number.

It is not a de Polignac number, because 4030721 - 2⁶ = 4030657 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 4030721.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4030781) 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, 22556 + ... + 22733.

It is an arithmetic number, because the mean of its divisors is an integer number (1019025).

Almost surely, 2^4030721 is an apocalyptic number.

It is an amenable number.

4030721 is a deficient number, since it is larger than the sum of its proper divisors (45379).

4030721 is an equidigital number, since it uses as much as digits as its factorization.

4030721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45378.

The product of its (nonzero) digits is 168, while the sum is 17.

The square root of 4030721 is about 2007.6655597982. The cubic root of 4030721 is about 159.1454571241.

The spelling of 4030721 in words is "four million, thirty thousand, seven hundred twenty-one".