1251881888400 has 720 divisors, whose sum is σ = 5122893572160. Its totient is φ = 279098265600.

The previous prime is 1251881888393. The next prime is 1251881888437. The reversal of 1251881888400 is 48881881521.

It is a happy number.

1251881888400 is a `hidden beast` number, since 1 + 2 + 51 + 8 + 8 + 188 + 8 + 400 = 666.

It is a tau number, because it is divible by the number of its divisors (720).

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 142595211 + ... + 142603989.

Almost surely, 2^{1251881888400} is an apocalyptic number.

1251881888400 is a gapful number since it is divisible by the number (10) 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 1251881888400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2561446786080).

1251881888400 is an abundant number, since it is smaller than the sum of its proper divisors (3871011683760).

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

1251881888400 is a wasteful number, since it uses less digits than its factorization.

1251881888400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9104 (or 9090 counting only the distinct ones).

The product of its (nonzero) digits is 1310720, while the sum is 54.

It can be divided in two parts, 12518 and 81888400, that added together give a palindrome (81900918).

The spelling of 1251881888400 in words is "one trillion, two hundred fifty-one billion, eight hundred eighty-one million, eight hundred eighty-eight thousand, four hundred".