251928940 has 48 divisors (see below), whose sum is σ = 548158464. Its totient is φ = 97156800.

The previous prime is 251928907. The next prime is 251928947. The reversal of 251928940 is 49829152.

It is a junction number, because it is equal to n+sod(n) for n = 251928893 and 251928902.

It is not an unprimeable number, because it can be changed into a prime (251928947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 214555 + ... + 215725.

It is an arithmetic number, because the mean of its divisors is an integer number (11419968).

Almost surely, 2^251928940 is an apocalyptic number.

251928940 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 251928940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (274079232).

251928940 is an abundant number, since it is smaller than the sum of its proper divisors (296229524).

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

251928940 is a wasteful number, since it uses less digits than its factorization.

251928940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1558 (or 1556 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 40.

The square root of 251928940 is about 15872.2695289615. The cubic root of 251928940 is about 631.5765837460.

The spelling of 251928940 in words is "two hundred fifty-one million, nine hundred twenty-eight thousand, nine hundred forty".