31121001121 has 4 divisors (see below), whose sum is σ = 35566858432. Its totient is φ = 26675143812.

The previous prime is 31121001077. The next prime is 31121001203. The reversal of 31121001121 is 12110012113.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12110012113 = 137 ⋅88394249.

It is a cyclic number.

It is not a de Polignac number, because 31121001121 - 2¹⁵ = 31120968353 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31121001221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2222928645 + ... + 2222928658.

It is an arithmetic number, because the mean of its divisors is an integer number (8891714608).

Almost surely, 2^31121001121 is an apocalyptic number.

It is an amenable number.

31121001121 is a deficient number, since it is larger than the sum of its proper divisors (4445857311).

31121001121 is an equidigital number, since it uses as much as digits as its factorization.

31121001121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4445857310.

The product of its (nonzero) digits is 12, while the sum is 13.

Adding to 31121001121 its reverse (12110012113), we get a palindrome (43231013234).

The spelling of 31121001121 in words is "thirty-one billion, one hundred twenty-one million, one thousand, one hundred twenty-one".