31311121100 has 144 divisors (see below), whose sum is σ = 79172432640. Its totient is φ = 10527072000.

The previous prime is 31311121069. The next prime is 31311121103. The reversal of 31311121100 is 112111313.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is not an unprimeable number, because it can be changed into a prime (31311121103) 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 47 ways as a sum of consecutive naturals, for example, 7562831 + ... + 7566969.

It is an arithmetic number, because the mean of its divisors is an integer number (549808560).

Almost surely, 2^31311121100 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31311121100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39586216320).

31311121100 is an abundant number, since it is smaller than the sum of its proper divisors (47861311540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31311121100 is a wasteful number, since it uses less digits than its factorization.

31311121100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4368 (or 4361 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 14.

Adding to 31311121100 its reverse (112111313), we get a palindrome (31423232413).

The spelling of 31311121100 in words is "thirty-one billion, three hundred eleven million, one hundred twenty-one thousand, one hundred".