31120042221 has 12 divisors (see below), whose sum is σ = 47317023520. Its totient is φ = 19654763400.

The previous prime is 31120042181. The next prime is 31120042231. The reversal of 31120042221 is 12224002113.

It is a happy number.

It is not a de Polignac number, because 31120042221 - 2⁶ = 31120042157 is a prime.

It is a super-2 number, since 2×31120042221² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 31120042194 and 31120042203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31120042231) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 90994105 + ... + 90994446.

Almost surely, 2^31120042221 is an apocalyptic number.

It is an amenable number.

31120042221 is a deficient number, since it is larger than the sum of its proper divisors (16196981299).

31120042221 is a wasteful number, since it uses less digits than its factorization.

31120042221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181988576 (or 181988573 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 31120042221 its reverse (12224002113), we get a palindrome (43344044334).

The spelling of 31120042221 in words is "thirty-one billion, one hundred twenty million, forty-two thousand, two hundred twenty-one".