25961072640 has 192 divisors, whose sum is σ = 87942516480. Its totient is φ = 6515589120.

The previous prime is 25961072639. The next prime is 25961072651. The reversal of 25961072640 is 4627016952.

It is a tau number, because it is divible by the number of its divisors (192).

It is a junction number, because it is equal to n+sod(n) for n = 25961072592 and 25961072601.

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 15 ways as a sum of consecutive naturals, for example, 497385 + ... + 547095.

It is an arithmetic number, because the mean of its divisors is an integer number (458033940).

Almost surely, 2^25961072640 is an apocalyptic number.

25961072640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25961072640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43971258240).

25961072640 is an abundant number, since it is smaller than the sum of its proper divisors (61981443840).

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

25961072640 is a wasteful number, since it uses less digits than its factorization.

25961072640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49758 (or 49738 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 42.

The spelling of 25961072640 in words is "twenty-five billion, nine hundred sixty-one million, seventy-two thousand, six hundred forty".