31231203111111 has 4 divisors (see below), whose sum is σ = 41641604148152. Its totient is φ = 20820802074072.

The previous prime is 31231203111103. The next prime is 31231203111247. The reversal of 31231203111111 is 11111130213213.

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

It is not a de Polignac number, because 31231203111111 - 2³ = 31231203111103 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31231203111811) 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, 5205200518516 + ... + 5205200518521.

It is an arithmetic number, because the mean of its divisors is an integer number (10410401037038).

Almost surely, 2^{31231203111111} is an apocalyptic number.

31231203111111 is a deficient number, since it is larger than the sum of its proper divisors (10410401037041).

31231203111111 is a wasteful number, since it uses less digits than its factorization.

31231203111111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10410401037040.

The product of its (nonzero) digits is 108, while the sum is 21.

Adding to 31231203111111 its reverse (11111130213213), we get a palindrome (42342333324324).

The spelling of 31231203111111 in words is "thirty-one trillion, two hundred thirty-one billion, two hundred three million, one hundred eleven thousand, one hundred eleven".