251241244220 has 96 divisors (see below), whose sum is σ = 575452684800. Its totient is φ = 91775980800.

The previous prime is 251241244217. The next prime is 251241244253. The reversal of 251241244220 is 22442142152.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6935555 + ... + 6971685.

It is an arithmetic number, because the mean of its divisors is an integer number (5994298800).

Almost surely, 2^251241244220 is an apocalyptic number.

251241244220 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 251241244220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (287726342400).

251241244220 is an abundant number, since it is smaller than the sum of its proper divisors (324211440580).

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

251241244220 is a wasteful number, since it uses less digits than its factorization.

251241244220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36819 (or 36817 counting only the distinct ones).

The product of its (nonzero) digits is 10240, while the sum is 29.

Adding to 251241244220 its reverse (22442142152), we get a palindrome (273683386372).

The spelling of 251241244220 in words is "two hundred fifty-one billion, two hundred forty-one million, two hundred forty-four thousand, two hundred twenty".