251023020 has 96 divisors (see below), whose sum is σ = 747242496. Its totient is φ = 62745600.

The previous prime is 251023009. The next prime is 251023039. The reversal of 251023020 is 20320152.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 439335 + ... + 439905.

It is an arithmetic number, because the mean of its divisors is an integer number (7783776).

Almost surely, 2^251023020 is an apocalyptic number.

251023020 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 251023020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (373621248).

251023020 is an abundant number, since it is smaller than the sum of its proper divisors (496219476).

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

251023020 is a wasteful number, since it uses less digits than its factorization.

251023020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1031 (or 1029 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 15.

The square root of 251023020 is about 15843.7060058561. The cubic root of 251023020 is about 630.8186384749.

Adding to 251023020 its reverse (20320152), we get a palindrome (271343172).

The spelling of 251023020 in words is "two hundred fifty-one million, twenty-three thousand, twenty".