31123221120 has 192 divisors, whose sum is σ = 109972605600. Its totient is φ = 8106448896.

The previous prime is 31123221049. The next prime is 31123221137. The reversal of 31123221120 is 2112232113.

31123221120 is a `hidden beast` number, since 311 + 2 + 322 + 11 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

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

It is a junction number, because it is equal to n+sod(n) for n = 31123221093 and 31123221102.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 184851 + ... + 310509.

Almost surely, 2^31123221120 is an apocalyptic number.

31123221120 is a gapful number since it is divisible by the number (30) 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 31123221120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54986302800).

31123221120 is an abundant number, since it is smaller than the sum of its proper divisors (78849384480).

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

31123221120 is a wasteful number, since it uses less digits than its factorization.

31123221120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125727 (or 125712 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 31123221120 its reverse (2112232113), we get a palindrome (33235453233).

The spelling of 31123221120 in words is "thirty-one billion, one hundred twenty-three million, two hundred twenty-one thousand, one hundred twenty".