251012242544 has 160 divisors (see below), whose sum is σ = 600556311936. Its totient is φ = 99181854720.

The previous prime is 251012242543. The next prime is 251012242553. The reversal of 251012242544 is 445242210152.

It is a self number, because there is not a number n which added to its sum of digits gives 251012242544.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251012242543) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 80425304 + ... + 80428424.

Almost surely, 2^251012242544 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 251012242544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (300278155968).

251012242544 is an abundant number, since it is smaller than the sum of its proper divisors (349544069392).

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

251012242544 is a wasteful number, since it uses less digits than its factorization.

251012242544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4003 (or 3997 counting only the distinct ones).

The product of its (nonzero) digits is 25600, while the sum is 32.

Adding to 251012242544 its reverse (445242210152), we get a palindrome (696254452696).

The spelling of 251012242544 in words is "two hundred fifty-one billion, twelve million, two hundred forty-two thousand, five hundred forty-four".