31312223 has 4 divisors (see below), whose sum is σ = 32673648. Its totient is φ = 29950800.

The previous prime is 31312219. The next prime is 31312243. The reversal of 31312223 is 32221313.

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

It is a cyclic number.

It is not a de Polignac number, because 31312223 - 2² = 31312219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31312243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 680678 + ... + 680723.

It is an arithmetic number, because the mean of its divisors is an integer number (8168412).

Almost surely, 2^31312223 is an apocalyptic number.

31312223 is a deficient number, since it is larger than the sum of its proper divisors (1361425).

31312223 is a wasteful number, since it uses less digits than its factorization.

31312223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1361424.

The product of its digits is 216, while the sum is 17.

The square root of 31312223 is about 5595.7325704504. The cubic root of 31312223 is about 315.1891800539.

Adding to 31312223 its reverse (32221313), we get a palindrome (63533536).

The spelling of 31312223 in words is "thirty-one million, three hundred twelve thousand, two hundred twenty-three".