31311120 has 80 divisors (see below), whose sum is σ = 97618752. Its totient is φ = 8302080.

The previous prime is 31311113. The next prime is 31311121. The reversal of 31311120 is 2111313.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 31311096 and 31311105.

It is not an unprimeable number, because it can be changed into a prime (31311121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 67690 + ... + 68150.

Almost surely, 2^31311120 is an apocalyptic number.

31311120 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 31311120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48809376).

31311120 is an abundant number, since it is smaller than the sum of its proper divisors (66307632).

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

31311120 is a wasteful number, since it uses less digits than its factorization.

31311120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 760 (or 754 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 12.

The square root of 31311120 is about 5595.6340123350. The cubic root of 31311120 is about 315.1854790737.

Adding to 31311120 its reverse (2111313), we get a palindrome (33422433).

The spelling of 31311120 in words is "thirty-one million, three hundred eleven thousand, one hundred twenty".