31302142121 has 4 divisors (see below), whose sum is σ = 32065609044. Its totient is φ = 30538675200.

The previous prime is 31302142063. The next prime is 31302142139. The reversal of 31302142121 is 12124120313.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17860986025 + 13441156096 = 133645^2 + 115936^2 .

It is a cyclic number.

It is not a de Polignac number, because 31302142121 - 2²² = 31297947817 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31302142093 and 31302142102.

It is not an unprimeable number, because it can be changed into a prime (31302142141) 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, 381733400 + ... + 381733481.

It is an arithmetic number, because the mean of its divisors is an integer number (8016402261).

Almost surely, 2^31302142121 is an apocalyptic number.

It is an amenable number.

31302142121 is a deficient number, since it is larger than the sum of its proper divisors (763466923).

31302142121 is an equidigital number, since it uses as much as digits as its factorization.

31302142121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 763466922.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 31302142121 its reverse (12124120313), we get a palindrome (43426262434).

The spelling of 31302142121 in words is "thirty-one billion, three hundred two million, one hundred forty-two thousand, one hundred twenty-one".