251234551240 has 64 divisors (see below), whose sum is σ = 571383590400. Its totient is φ = 99409348608.

The previous prime is 251234551199. The next prime is 251234551273. The reversal of 251234551240 is 42155432152.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 251234551196 and 251234551205.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8548491 + ... + 8577829.

It is an arithmetic number, because the mean of its divisors is an integer number (8927868600).

Almost surely, 2^251234551240 is an apocalyptic number.

251234551240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251234551240 is an abundant number, since it is smaller than the sum of its proper divisors (320149039160).

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

251234551240 is a wasteful number, since it uses less digits than its factorization.

251234551240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31654 (or 31650 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 34.

Adding to 251234551240 its reverse (42155432152), we get a palindrome (293389983392).

The spelling of 251234551240 in words is "two hundred fifty-one billion, two hundred thirty-four million, five hundred fifty-one thousand, two hundred forty".