251422740 has 144 divisors (see below), whose sum is σ = 788755968. Its totient is φ = 64791552.

The previous prime is 251422727. The next prime is 251422751. The reversal of 251422740 is 47224152.

251422740 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 955849 + ... + 956111.

It is an arithmetic number, because the mean of its divisors is an integer number (5477472).

Almost surely, 2^251422740 is an apocalyptic number.

251422740 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 251422740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (394377984).

251422740 is an abundant number, since it is smaller than the sum of its proper divisors (537333228).

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

251422740 is a wasteful number, since it uses less digits than its factorization.

251422740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438 (or 433 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 27.

The square root of 251422740 is about 15856.3154610395. The cubic root of 251422740 is about 631.1532918543.

Adding to 251422740 its reverse (47224152), we get a palindrome (298646892).

The spelling of 251422740 in words is "two hundred fifty-one million, four hundred twenty-two thousand, seven hundred forty".