5251221 has 6 divisors (see below), whose sum is σ = 7585110. Its totient is φ = 3500808.

The previous prime is 5251217. The next prime is 5251229. The reversal of 5251221 is 1221525.

It can be written as a sum of positive squares in only one way, i.e., 4223025 + 1028196 = 2055^2 + 1014^2 .

It is not a de Polignac number, because 5251221 - 2² = 5251217 is a prime.

5251221 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 5251194 and 5251203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5251229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 291726 + ... + 291743.

It is an arithmetic number, because the mean of its divisors is an integer number (1264185).

Almost surely, 2^5251221 is an apocalyptic number.

It is an amenable number.

5251221 is a deficient number, since it is larger than the sum of its proper divisors (2333889).

5251221 is a wasteful number, since it uses less digits than its factorization.

5251221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 583475 (or 583472 counting only the distinct ones).

The product of its digits is 200, while the sum is 18.

The square root of 5251221 is about 2291.5542760319. The cubic root of 5251221 is about 173.8148049413.

Adding to 5251221 its reverse (1221525), we get a palindrome (6472746).

The spelling of 5251221 in words is "five million, two hundred fifty-one thousand, two hundred twenty-one".