25665031040 has 128 divisors (see below), whose sum is σ = 67116816000. Its totient is φ = 9307146240.

The previous prime is 25665031039. The next prime is 25665031103. The reversal of 25665031040 is 4013056652.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 25665030988 and 25665031006.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2663351 + ... + 2672969.

It is an arithmetic number, because the mean of its divisors is an integer number (524350125).

Almost surely, 2^25665031040 is an apocalyptic number.

25665031040 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 25665031040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33558408000).

25665031040 is an abundant number, since it is smaller than the sum of its proper divisors (41451784960).

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

25665031040 is a wasteful number, since it uses less digits than its factorization.

25665031040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10028 (or 10016 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 32.

Adding to 25665031040 its reverse (4013056652), we get a palindrome (29678087692).

The spelling of 25665031040 in words is "twenty-five billion, six hundred sixty-five million, thirty-one thousand, forty".