5518991 has 4 divisors (see below), whose sum is σ = 5601432. Its totient is φ = 5436552.

The previous prime is 5518967. The next prime is 5519029. The reversal of 5518991 is 1998155.

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

It is a cyclic number.

It is not a de Polignac number, because 5518991 - 2⁶ = 5518927 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5518951) 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, 41120 + ... + 41253.

It is an arithmetic number, because the mean of its divisors is an integer number (1400358).

Almost surely, 2^5518991 is an apocalyptic number.

5518991 is a deficient number, since it is larger than the sum of its proper divisors (82441).

5518991 is an equidigital number, since it uses as much as digits as its factorization.

5518991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82440.

The product of its digits is 16200, while the sum is 38.

The square root of 5518991 is about 2349.2532856208. The cubic root of 5518991 is about 176.7203495734.

The spelling of 5518991 in words is "five million, five hundred eighteen thousand, nine hundred ninety-one".