251430040 has 64 divisors (see below), whose sum is σ = 610092000. Its totient is φ = 92943360.

The previous prime is 251430037. The next prime is 251430071. The reversal of 251430040 is 40034152.

251430040 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a congruent number.

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, 27126 + ... + 35194.

Almost surely, 2^251430040 is an apocalyptic number.

251430040 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 251430040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (305046000).

251430040 is an abundant number, since it is smaller than the sum of its proper divisors (358661960).

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

251430040 is a wasteful number, since it uses less digits than its factorization.

251430040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8140 (or 8136 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 251430040 is about 15856.5456515598. The cubic root of 251430040 is about 631.1594002575.

Adding to 251430040 its reverse (40034152), we get a palindrome (291464192).

The spelling of 251430040 in words is "two hundred fifty-one million, four hundred thirty thousand, forty".