3131310221 has 4 divisors (see below), whose sum is σ = 3372180252. Its totient is φ = 2890440192.

The previous prime is 3131310211. The next prime is 3131310227. The reversal of 3131310221 is 1220131313.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1220131313 = 479 ⋅2547247.

It can be written as a sum of positive squares in 2 ways, for example, as 594676996 + 2536633225 = 24386^2 + 50365^2 .

It is a cyclic number.

It is not a de Polignac number, because 3131310221 - 2⁶ = 3131310157 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 3131310221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3131310227) 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, 120434996 + ... + 120435021.

It is an arithmetic number, because the mean of its divisors is an integer number (843045063).

Almost surely, 2^3131310221 is an apocalyptic number.

It is an amenable number.

3131310221 is a deficient number, since it is larger than the sum of its proper divisors (240870031).

3131310221 is a wasteful number, since it uses less digits than its factorization.

3131310221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240870030.

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 3131310221 is about 55958.1113065836. Note that the first 3 decimals coincide. The cubic root of 3131310221 is about 1462.9922713853.

Adding to 3131310221 its reverse (1220131313), we get a palindrome (4351441534).

The spelling of 3131310221 in words is "three billion, one hundred thirty-one million, three hundred ten thousand, two hundred twenty-one".