20121143240 has 96 divisors (see below), whose sum is σ = 50256332280. Its totient is φ = 7244160000.

The previous prime is 20121143239. The next prime is 20121143243. The reversal of 20121143240 is 4234112102.

It can be written as a sum of positive squares in 4 ways, for example, as 20054524996 + 66618244 = 141614^2 + 8162^2 .

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

It is not an unprimeable number, because it can be changed into a prime (20121143243) 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, 468260 + ... + 509420.

Almost surely, 2^20121143240 is an apocalyptic number.

20121143240 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 20121143240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25128166140).

20121143240 is an abundant number, since it is smaller than the sum of its proper divisors (30135189040).

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

20121143240 is a wasteful number, since it uses less digits than its factorization.

20121143240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41295 (or 41280 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 20121143240 its reverse (4234112102), we get a palindrome (24355255342).

It can be divided in two parts, 20121 and 143240, that added together give a palindrome (163361).

The spelling of 20121143240 in words is "twenty billion, one hundred twenty-one million, one hundred forty-three thousand, two hundred forty".