20131111312 has 20 divisors (see below), whose sum is σ = 42004338460. Its totient is φ = 9291282048.

The previous prime is 20131111243. The next prime is 20131111313. The reversal of 20131111312 is 21311113102.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 3359825296 + 16771286016 = 57964^2 + 129504^2 .

It is a super-2 number, since 2×20131111312² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is not an unprimeable number, because it can be changed into a prime (20131111313) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48391887 + ... + 48392302.

It is an arithmetic number, because the mean of its divisors is an integer number (2100216923).

Almost surely, 2^20131111312 is an apocalyptic number.

It is an amenable number.

20131111312 is an abundant number, since it is smaller than the sum of its proper divisors (21873227148).

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

20131111312 is a wasteful number, since it uses less digits than its factorization.

20131111312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96784210 (or 96784204 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 20131111312 its reverse (21311113102), we get a palindrome (41442224414).

The spelling of 20131111312 in words is "twenty billion, one hundred thirty-one million, one hundred eleven thousand, three hundred twelve".