31230121121 has 4 divisors (see below), whose sum is σ = 31251645744. Its totient is φ = 31208596500.

The previous prime is 31230121081. The next prime is 31230121123. The reversal of 31230121121 is 12112103213.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31230121121 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31230121121.

It is not an unprimeable number, because it can be changed into a prime (31230121123) 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, 10760135 + ... + 10763036.

It is an arithmetic number, because the mean of its divisors is an integer number (7812911436).

Almost surely, 2^31230121121 is an apocalyptic number.

It is an amenable number.

31230121121 is a deficient number, since it is larger than the sum of its proper divisors (21524623).

31230121121 is a wasteful number, since it uses less digits than its factorization.

31230121121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21524622.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 31230121121 its reverse (12112103213), we get a palindrome (43342224334).

The spelling of 31230121121 in words is "thirty-one billion, two hundred thirty million, one hundred twenty-one thousand, one hundred twenty-one".