2251521000 has 96 divisors (see below), whose sum is σ = 7610171400. Its totient is φ = 600403200.

The previous prime is 2251520989. The next prime is 2251521001. The reversal of 2251521000 is 1251522.

It can be written as a sum of positive squares in 4 ways, for example, as 1466736804 + 784784196 = 38298^2 + 28014^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (2251521001) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 116085 + ... + 134084.

Almost surely, 2^2251521000 is an apocalyptic number.

2251521000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2251521000 is an abundant number, since it is smaller than the sum of its proper divisors (5358650400).

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

2251521000 is a wasteful number, since it uses less digits than its factorization.

2251521000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250196 (or 250179 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 2251521000 is about 47450.1949416438. The cubic root of 2251521000 is about 1310.6659007923.

Adding to 2251521000 its reverse (1251522), we get a palindrome (2252772522).

The spelling of 2251521000 in words is "two billion, two hundred fifty-one million, five hundred twenty-one thousand".