31205133 has 12 divisors (see below), whose sum is σ = 46033728. Its totient is φ = 20360520.

The previous prime is 31205129. The next prime is 31205173. The reversal of 31205133 is 33150213.

It is not a de Polignac number, because 31205133 - 2² = 31205129 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31205113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36463 + ... + 37308.

It is an arithmetic number, because the mean of its divisors is an integer number (3836144).

Almost surely, 2^31205133 is an apocalyptic number.

It is an amenable number.

31205133 is a deficient number, since it is larger than the sum of its proper divisors (14828595).

31205133 is a wasteful number, since it uses less digits than its factorization.

31205133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73824 (or 73821 counting only the distinct ones).

The product of its (nonzero) digits is 270, while the sum is 18.

The square root of 31205133 is about 5586.1554758170. The cubic root of 31205133 is about 314.8294465990.

Adding to 31205133 its reverse (33150213), we get a palindrome (64355346).

The spelling of 31205133 in words is "thirty-one million, two hundred five thousand, one hundred thirty-three".