3131261 has 4 divisors (see below), whose sum is σ = 3578592. Its totient is φ = 2683932.

The previous prime is 3131251. The next prime is 3131263. The reversal of 3131261 is 1621313.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1621313 = 89 ⋅18217.

It is a cyclic number.

It is not a de Polignac number, because 3131261 - 2¹⁸ = 2869117 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 (3131263) 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, 223655 + ... + 223668.

It is an arithmetic number, because the mean of its divisors is an integer number (894648).

Almost surely, 2^3131261 is an apocalyptic number.

It is an amenable number.

3131261 is a deficient number, since it is larger than the sum of its proper divisors (447331).

3131261 is an equidigital number, since it uses as much as digits as its factorization.

3131261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 447330.

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

The square root of 3131261 is about 1769.5369450791. The cubic root of 3131261 is about 146.2984605763.

Adding to 3131261 its reverse (1621313), we get a palindrome (4752574).

The spelling of 3131261 in words is "three million, one hundred thirty-one thousand, two hundred sixty-one".