12031100172 has 144 divisors (see below), whose sum is σ = 37655933952. Its totient is φ = 3153893760.

The previous prime is 12031100171. The next prime is 12031100203. The reversal of 12031100172 is 27100113021.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (12031100171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 536097 + ... + 558087.

Almost surely, 2^12031100172 is an apocalyptic number.

12031100172 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12031100172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18827966976).

12031100172 is an abundant number, since it is smaller than the sum of its proper divisors (25624833780).

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

12031100172 is a wasteful number, since it uses less digits than its factorization.

12031100172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22188 (or 22183 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 18.

Adding to 12031100172 its reverse (27100113021), we get a palindrome (39131213193).

The spelling of 12031100172 in words is "twelve billion, thirty-one million, one hundred thousand, one hundred seventy-two".