25445133440 has 32 divisors (see below), whose sum is σ = 60829773660. Its totient is φ = 10178053120.

The previous prime is 25445133409. The next prime is 25445133449. The reversal of 25445133440 is 4433154452.

It can be written as a sum of positive squares in 2 ways, for example, as 25316628544 + 128504896 = 159112^2 + 11336^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a self number, because there is not a number n which added to its sum of digits gives 25445133440.

It is not an unprimeable number, because it can be changed into a prime (25445133449) 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 3 ways as a sum of consecutive naturals, for example, 19878371 + ... + 19879650.

Almost surely, 2^25445133440 is an apocalyptic number.

25445133440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25445133440 is an abundant number, since it is smaller than the sum of its proper divisors (35384640220).

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

25445133440 is an equidigital number, since it uses as much as digits as its factorization.

25445133440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39758040 (or 39758028 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 35.

Adding to 25445133440 its reverse (4433154452), we get a palindrome (29878287892).

The spelling of 25445133440 in words is "twenty-five billion, four hundred forty-five million, one hundred thirty-three thousand, four hundred forty".