20131121140 has 72 divisors (see below), whose sum is σ = 46018603008. Its totient is φ = 7393875840.

The previous prime is 20131121117. The next prime is 20131121141. The reversal of 20131121140 is 4112113102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20131121141) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 629989 + ... + 661171.

It is an arithmetic number, because the mean of its divisors is an integer number (639147264).

Almost surely, 2^20131121140 is an apocalyptic number.

20131121140 is a gapful number since it is divisible by the number (20) 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 20131121140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23009301504).

20131121140 is an abundant number, since it is smaller than the sum of its proper divisors (25887481868).

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

20131121140 is a wasteful number, since it uses less digits than its factorization.

20131121140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31409 (or 31394 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 20131121140 its reverse (4112113102), we get a palindrome (24243234242).

The spelling of 20131121140 in words is "twenty billion, one hundred thirty-one million, one hundred twenty-one thousand, one hundred forty".