31121361 has 8 divisors (see below), whose sum is σ = 46105760.
Its totient is φ = 20747556.
The previous prime is 31121357. The next prime is 31121371. The reversal of 31121361 is 16312113.
Adding to 31121361 its reverse (16312113), we get a palindrome (47433474).
It is not a de Polignac number, because 31121361 - 22 = 31121357 is a prime.
It is a super-2 number, since 2×311213612 = 1937078220984642, which contains 22 as substring.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (31121341) 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 7 ways as a sum of consecutive naturals, for example, 576295 + ... + 576348.
It is an arithmetic number, because the mean of its divisors is an integer number (5763220).
Almost surely, 231121361 is an apocalyptic number.
It is an amenable number.
31121361 is a deficient number, since it is larger than the sum of its proper divisors (14984399).
31121361 is a wasteful number, since it uses less digits than its factorization.
31121361 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 1152652 (or 1152646 counting only the distinct ones).
The product of its digits is 108, while the sum is 18.
The square root of 31121361 is about 5578.6522565939.
The cubic root of 31121361 is about 314.5474681137.
The spelling of 31121361 in words is "thirty-one million, one hundred twenty-one thousand, three hundred sixty-one".