4521391 has 8 divisors (see below), whose sum is σ = 5218304. Its totient is φ = 3837240.

The previous prime is 4521389. The next prime is 4521403. The reversal of 4521391 is 1931254.

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

It is a cyclic number.

It is not a de Polignac number, because 4521391 - 2¹ = 4521389 is a prime.

It is a super-3 number, since 3×4521391³ (a number of 21 digits) contains 333 as substring.

4521391 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4521301) 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, 2415 + ... + 3856.

It is an arithmetic number, because the mean of its divisors is an integer number (652288).

Almost surely, 2^4521391 is an apocalyptic number.

4521391 is a deficient number, since it is larger than the sum of its proper divisors (696913).

4521391 is a wasteful number, since it uses less digits than its factorization.

4521391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6381.

The product of its digits is 1080, while the sum is 25.

The square root of 4521391 is about 2126.3562730643. The cubic root of 4521391 is about 165.3575472723.

The spelling of 4521391 in words is "four million, five hundred twenty-one thousand, three hundred ninety-one".