5518721 has 8 divisors (see below), whose sum is σ = 6256320. Its totient is φ = 4825872.

The previous prime is 5518687. The next prime is 5518817. The reversal of 5518721 is 1278155.

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 5518721 - 2¹⁰ = 5517697 is a prime.

It is not an unprimeable number, because it can be changed into a prime (5518021) 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, 10925 + ... + 11418.

It is an arithmetic number, because the mean of its divisors is an integer number (782040).

Almost surely, 2^5518721 is an apocalyptic number.

It is an amenable number.

5518721 is a deficient number, since it is larger than the sum of its proper divisors (737599).

5518721 is a wasteful number, since it uses less digits than its factorization.

5518721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22375.

The product of its digits is 2800, while the sum is 29.

The square root of 5518721 is about 2349.1958198498. The cubic root of 5518721 is about 176.7174676896.

The spelling of 5518721 in words is "five million, five hundred eighteen thousand, seven hundred twenty-one".