251049720 has 96 divisors (see below), whose sum is σ = 767405520. Its totient is φ = 65702400.

The previous prime is 251049719. The next prime is 251049739. The reversal of 251049720 is 27940152.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 417420 + ... + 418020.

Almost surely, 2^251049720 is an apocalyptic number.

251049720 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 251049720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (383702760).

251049720 is an abundant number, since it is smaller than the sum of its proper divisors (516355800).

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

251049720 is a wasteful number, since it uses less digits than its factorization.

251049720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 733 (or 670 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 30.

The square root of 251049720 is about 15844.5485893414. The cubic root of 251049720 is about 630.8410033036.

Adding to 251049720 its reverse (27940152), we get a palindrome (278989872).

The spelling of 251049720 in words is "two hundred fifty-one million, forty-nine thousand, seven hundred twenty".