31320120 has 128 divisors (see below), whose sum is σ = 107231040. Its totient is φ = 7249920.

The previous prime is 31320109. The next prime is 31320173. The reversal of 31320120 is 2102313.

It is a happy number.

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 = 31320096 and 31320105.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 25930 + ... + 27110.

Almost surely, 2^31320120 is an apocalyptic number.

31320120 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 31320120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53615520).

31320120 is an abundant number, since it is smaller than the sum of its proper divisors (75910920).

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

31320120 is a wasteful number, since it uses less digits than its factorization.

31320120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1225 (or 1221 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 31320120 is about 5596.4381529684. The cubic root of 31320120 is about 315.2156749228.

Adding to 31320120 its reverse (2102313), we get a palindrome (33422433).

The spelling of 31320120 in words is "thirty-one million, three hundred twenty thousand, one hundred twenty".