251043140 has 24 divisors (see below), whose sum is σ = 545370840. Its totient is φ = 96954368.

The previous prime is 251043127. The next prime is 251043167. The reversal of 251043140 is 41340152.

It can be written as a sum of positive squares in 4 ways, for example, as 18541636 + 232501504 = 4306^2 + 15248^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 215837 + ... + 216996.

It is an arithmetic number, because the mean of its divisors is an integer number (22723785).

Almost surely, 2^251043140 is an apocalyptic number.

251043140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251043140 is an abundant number, since it is smaller than the sum of its proper divisors (294327700).

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

251043140 is a wasteful number, since it uses less digits than its factorization.

251043140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432871 (or 432869 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 251043140 is about 15844.3409455869. The cubic root of 251043140 is about 630.8354918189.

Adding to 251043140 its reverse (41340152), we get a palindrome (292383292).

The spelling of 251043140 in words is "two hundred fifty-one million, forty-three thousand, one hundred forty".