31020121021013 has 4 divisors (see below), whose sum is σ = 31020988534080. Its totient is φ = 31019253507948.

The previous prime is 31020121020943. The next prime is 31020121021049. The reversal of 31020121021013 is 31012012102013.

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 31020121021013 - 2¹⁴ = 31020121004629 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31020121020982 and 31020121021000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31020121021093) 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, 433702895 + ... + 433774412.

It is an arithmetic number, because the mean of its divisors is an integer number (7755247133520).

Almost surely, 2^{31020121021013} is an apocalyptic number.

It is an amenable number.

31020121021013 is a deficient number, since it is larger than the sum of its proper divisors (867513067).

31020121021013 is an equidigital number, since it uses as much as digits as its factorization.

31020121021013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 867513066.

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

Adding to 31020121021013 its reverse (31012012102013), we get a palindrome (62032133123026).

The spelling of 31020121021013 in words is "thirty-one trillion, twenty billion, one hundred twenty-one million, twenty-one thousand, thirteen".