25705412640 has 192 divisors, whose sum is σ = 91494748800. Its totient is φ = 6738527232.

The previous prime is 25705412633. The next prime is 25705412641. The reversal of 25705412640 is 4621450752.

It is a happy number.

25705412640 is a `hidden beast` number, since 2 + 5 + 7 + 0 + 5 + 4 + 1 + 2 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 25705412595 and 25705412604.

It is not an unprimeable number, because it can be changed into a prime (25705412641) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 204454 + ... + 305306.

It is an arithmetic number, because the mean of its divisors is an integer number (476535150).

Almost surely, 2^25705412640 is an apocalyptic number.

25705412640 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 25705412640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45747374400).

25705412640 is an abundant number, since it is smaller than the sum of its proper divisors (65789336160).

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

25705412640 is a wasteful number, since it uses less digits than its factorization.

25705412640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100936 (or 100922 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 36.

The spelling of 25705412640 in words is "twenty-five billion, seven hundred five million, four hundred twelve thousand, six hundred forty".