251251133742 has 512 divisors, whose sum is σ = 707788800000. Its totient is φ = 65879049600.

The previous prime is 251251133729. The next prime is 251251133747. The reversal of 251251133742 is 247331152152.

251251133742 is a `hidden beast` number, since 2 + 512 + 5 + 1 + 133 + 7 + 4 + 2 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 251251133697 and 251251133706.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251251133747) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 1315450867 + ... + 1315451057.

It is an arithmetic number, because the mean of its divisors is an integer number (1382400000).

Almost surely, 2^251251133742 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 251251133742, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (353894400000).

251251133742 is an abundant number, since it is smaller than the sum of its proper divisors (456537666258).

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

251251133742 is a wasteful number, since it uses less digits than its factorization.

251251133742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362 (or 342 counting only the distinct ones).

The product of its digits is 50400, while the sum is 36.

Adding to 251251133742 its reverse (247331152152), we get a palindrome (498582285894).

The spelling of 251251133742 in words is "two hundred fifty-one billion, two hundred fifty-one million, one hundred thirty-three thousand, seven hundred forty-two".