31231122011 has 4 divisors (see below), whose sum is σ = 31238268192. Its totient is φ = 31223975832.

The previous prime is 31231122001. The next prime is 31231122029. The reversal of 31231122011 is 11022113213.

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

It is a cyclic number.

It is not a de Polignac number, because 31231122011 - 2¹⁴ = 31231105627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31231122001) 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, 3566531 + ... + 3575276.

It is an arithmetic number, because the mean of its divisors is an integer number (7809567048).

Almost surely, 2^31231122011 is an apocalyptic number.

31231122011 is a deficient number, since it is larger than the sum of its proper divisors (7146181).

31231122011 is an equidigital number, since it uses as much as digits as its factorization.

31231122011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7146180.

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

Adding to 31231122011 its reverse (11022113213), we get a palindrome (42253235224).

The spelling of 31231122011 in words is "thirty-one billion, two hundred thirty-one million, one hundred twenty-two thousand, eleven".