31123304120 has 32 divisors (see below), whose sum is σ = 71517384000. Its totient is φ = 12184441728.

The previous prime is 31123304119. The next prime is 31123304123. The reversal of 31123304120 is 2140332113.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 31123304092 and 31123304101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31123304123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8275595 + ... + 8279354.

It is an arithmetic number, because the mean of its divisors is an integer number (2234918250).

Almost surely, 2^31123304120 is an apocalyptic number.

It is an amenable number.

31123304120 is an abundant number, since it is smaller than the sum of its proper divisors (40394079880).

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

31123304120 is a wasteful number, since it uses less digits than its factorization.

31123304120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16555007 (or 16555003 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 31123304120 its reverse (2140332113), we get a palindrome (33263636233).

The spelling of 31123304120 in words is "thirty-one billion, one hundred twenty-three million, three hundred four thousand, one hundred twenty".