251051522020 has 48 divisors (see below), whose sum is σ = 569576795760. Its totient is φ = 92399763456.

The previous prime is 251051521999. The next prime is 251051522077. The reversal of 251051522020 is 20225150152.

It can be written as a sum of positive squares in 8 ways, for example, as 39795462144 + 211256059876 = 199488^2 + 459626^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1461085 + ... + 1623844.

It is an arithmetic number, because the mean of its divisors is an integer number (11866183245).

Almost surely, 2^251051522020 is an apocalyptic number.

251051522020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251051522020 is an abundant number, since it is smaller than the sum of its proper divisors (318525273740).

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

251051522020 is a wasteful number, since it uses less digits than its factorization.

251051522020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3085264 (or 3085262 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 25.

Adding to 251051522020 its reverse (20225150152), we get a palindrome (271276672172).

The spelling of 251051522020 in words is "two hundred fifty-one billion, fifty-one million, five hundred twenty-two thousand, twenty".