2531321 has 4 divisors (see below), whose sum is σ = 2726052. Its totient is φ = 2336592.

The previous prime is 2531293. The next prime is 2531369. The reversal of 2531321 is 1231352.

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

It can be written as a sum of positive squares in 2 ways, for example, as 469225 + 2062096 = 685^2 + 1436^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2531321 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2531321.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2531371) 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, 97346 + ... + 97371.

It is an arithmetic number, because the mean of its divisors is an integer number (681513).

2^2531321 is an apocalyptic number.

It is an amenable number.

2531321 is a deficient number, since it is larger than the sum of its proper divisors (194731).

2531321 is a wasteful number, since it uses less digits than its factorization.

2531321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194730.

The product of its digits is 180, while the sum is 17.

The square root of 2531321 is about 1591.0125706606. The cubic root of 2531321 is about 136.2853186783.

Adding to 2531321 its reverse (1231352), we get a palindrome (3762673).

The spelling of 2531321 in words is "two million, five hundred thirty-one thousand, three hundred twenty-one".