25906645440 has 1008 divisors, whose sum is σ = 106505508096. Its totient is φ = 5750784000.

The previous prime is 25906645421. The next prime is 25906645451. The reversal of 25906645440 is 4454660952.

25906645440 is a `hidden beast` number, since 2 + 590 + 6 + 6 + 4 + 54 + 4 + 0 = 666.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 256501390 + ... + 256501490.

Almost surely, 2^25906645440 is an apocalyptic number.

25906645440 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 25906645440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53252754048).

25906645440 is an abundant number, since it is smaller than the sum of its proper divisors (80598862656).

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

25906645440 is a wasteful number, since it uses less digits than its factorization.

25906645440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198 (or 172 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 45.

The spelling of 25906645440 in words is "twenty-five billion, nine hundred six million, six hundred forty-five thousand, four hundred forty".