5191221 has 8 divisors (see below), whose sum is σ = 7910464. Its totient is φ = 2966400.

The previous prime is 5191213. The next prime is 5191231. The reversal of 5191221 is 1221915.

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

It is not a de Polignac number, because 5191221 - 2³ = 5191213 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 247201 = 5191221 / (5 + 1 + 9 + 1 + 2 + 2 + 1).

It is a Duffinian number.

It is a Curzon number.

5191221 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5191231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 123580 + ... + 123621.

It is an arithmetic number, because the mean of its divisors is an integer number (988808).

Almost surely, 2^5191221 is an apocalyptic number.

It is an amenable number.

5191221 is a deficient number, since it is larger than the sum of its proper divisors (2719243).

5191221 is a wasteful number, since it uses less digits than its factorization.

5191221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 247211.

The product of its digits is 180, while the sum is 21.

The square root of 5191221 is about 2278.4251139768. The cubic root of 5191221 is about 173.1502698281.

The spelling of 5191221 in words is "five million, one hundred ninety-one thousand, two hundred twenty-one".