31145331 has 12 divisors (see below), whose sum is σ = 48307272. Its totient is φ = 17797248.

The previous prime is 31145329. The next prime is 31145339. The reversal of 31145331 is 13354113.

It is not a de Polignac number, because 31145331 - 2¹ = 31145329 is a prime.

It is a super-2 number, since 2×31145331² = 1940063286199122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 31145298 and 31145307.

It is not an unprimeable number, because it can be changed into a prime (31145339) 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 11 ways as a sum of consecutive naturals, for example, 105790 + ... + 106083.

It is an arithmetic number, because the mean of its divisors is an integer number (4025606).

Almost surely, 2^31145331 is an apocalyptic number.

31145331 is a deficient number, since it is larger than the sum of its proper divisors (17161941).

31145331 is a wasteful number, since it uses less digits than its factorization.

31145331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211890 (or 211883 counting only the distinct ones).

The product of its digits is 540, while the sum is 21.

The square root of 31145331 is about 5580.8002114392. The cubic root of 31145331 is about 314.6282033138.

Adding to 31145331 its reverse (13354113), we get a palindrome (44499444).

The spelling of 31145331 in words is "thirty-one million, one hundred forty-five thousand, three hundred thirty-one".