25665321616 has 75 divisors (see below), whose sum is σ = 54864629715. Its totient is φ = 11630810400.

The previous prime is 25665321611. The next prime is 25665321629. The reversal of 25665321616 is 61612356652.

The square root of 25665321616 is 160204.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25665321611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 77538571 + ... + 77538901.

Almost surely, 2^25665321616 is an apocalyptic number.

25665321616 is the 160204-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25665321616

25665321616 is an abundant number, since it is smaller than the sum of its proper divisors (29199308099).

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

25665321616 is an frugal number, since it uses more digits than its factorization.

25665321616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 714 (or 344 counting only the distinct ones).

The product of its digits is 388800, while the sum is 43.

The spelling of 25665321616 in words is "twenty-five billion, six hundred sixty-five million, three hundred twenty-one thousand, six hundred sixteen".