31228689 has 4 divisors (see below), whose sum is σ = 41638256. Its totient is φ = 20819124.

The previous prime is 31228669. The next prime is 31228693. The reversal of 31228689 is 98682213.

It is a happy number.

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.

It is not a de Polignac number, because 31228689 - 2⁵ = 31228657 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (31228619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5204779 + ... + 5204784.

It is an arithmetic number, because the mean of its divisors is an integer number (10409564).

Almost surely, 2^31228689 is an apocalyptic number.

It is an amenable number.

31228689 is a deficient number, since it is larger than the sum of its proper divisors (10409567).

31228689 is a wasteful number, since it uses less digits than its factorization.

31228689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10409566.

The product of its digits is 41472, while the sum is 39.

The square root of 31228689 is about 5588.2635048824. The cubic root of 31228689 is about 314.9086457182.

It can be divided in two parts, 3122 and 8689, that added together give a palindrome (11811).

The spelling of 31228689 in words is "thirty-one million, two hundred twenty-eight thousand, six hundred eighty-nine".