31020321121 has 4 divisors (see below), whose sum is σ = 31026938544. Its totient is φ = 31013703700.

The previous prime is 31020321103. The next prime is 31020321161. The reversal of 31020321121 is 12112302013.

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 not a de Polignac number, because 31020321121 - 2¹¹ = 31020319073 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31020321095 and 31020321104.

It is not an unprimeable number, because it can be changed into a prime (31020321161) 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 3 ways as a sum of consecutive naturals, for example, 3301675 + ... + 3311056.

It is an arithmetic number, because the mean of its divisors is an integer number (7756734636).

Almost surely, 2^31020321121 is an apocalyptic number.

It is an amenable number.

31020321121 is a deficient number, since it is larger than the sum of its proper divisors (6617423).

31020321121 is an equidigital number, since it uses as much as digits as its factorization.

31020321121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6617422.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 31020321121 its reverse (12112302013), we get a palindrome (43132623134).

The spelling of 31020321121 in words is "thirty-one billion, twenty million, three hundred twenty-one thousand, one hundred twenty-one".