20121142400 has 96 divisors (see below), whose sum is σ = 49866795300. Its totient is φ = 8022343680.

The previous prime is 20121142399. The next prime is 20121142403. The reversal of 20121142400 is 424112102.

It can be written as a sum of positive squares in 6 ways, for example, as 140754496 + 19980387904 = 11864^2 + 141352^2 .

It is not an unprimeable number, because it can be changed into a prime (20121142403) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 991556 + ... + 1011644.

Almost surely, 2^20121142400 is an apocalyptic number.

20121142400 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 20121142400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24933397650).

20121142400 is an abundant number, since it is smaller than the sum of its proper divisors (29745652900).

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

20121142400 is a wasteful number, since it uses less digits than its factorization.

20121142400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20426 (or 20409 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 20121142400 its reverse (424112102), we get a palindrome (20545254502).

The spelling of 20121142400 in words is "twenty billion, one hundred twenty-one million, one hundred forty-two thousand, four hundred".