31320189 has 40 divisors (see below), whose sum is σ = 50413440. Its totient is φ = 19315584.

The previous prime is 31320173. The next prime is 31320193. The reversal of 31320189 is 98102313.

It is not a de Polignac number, because 31320189 - 2⁴ = 31320173 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31320109) 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 39 ways as a sum of consecutive naturals, for example, 72117 + ... + 72549.

It is an arithmetic number, because the mean of its divisors is an integer number (1260336).

Almost surely, 2^31320189 is an apocalyptic number.

It is an amenable number.

31320189 is a deficient number, since it is larger than the sum of its proper divisors (19093251).

31320189 is a wasteful number, since it uses less digits than its factorization.

31320189 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 511 (or 502 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 31320189 is about 5596.4443176002. Note that the first 3 decimals coincide. The cubic root of 31320189 is about 315.2159064020.

It can be divided in two parts, 313 and 20189, that added together give a palindrome (20502).

The spelling of 31320189 in words is "thirty-one million, three hundred twenty thousand, one hundred eighty-nine".