21525245344 has 36 divisors (see below), whose sum is σ = 43436750742. Its totient is φ = 10500093440.

The previous prime is 21525245333. The next prime is 21525245363. The reversal of 21525245344 is 44354252512.

It can be written as a sum of positive squares in 3 ways, for example, as 12412633744 + 9112611600 = 111412^2 + 95460^2 .

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 146287 + ... + 253870.

Almost surely, 2^21525245344 is an apocalyptic number.

It is an amenable number.

21525245344 is an abundant number, since it is smaller than the sum of its proper divisors (21911505398).

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

21525245344 is an equidigital number, since it uses as much as digits as its factorization.

21525245344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 400249 (or 400200 counting only the distinct ones).

The product of its digits is 192000, while the sum is 37.

Adding to 21525245344 its reverse (44354252512), we get a palindrome (65879497856).

The spelling of 21525245344 in words is "twenty-one billion, five hundred twenty-five million, two hundred forty-five thousand, three hundred forty-four".