25994534307840 has 720 divisors, whose sum is σ = 108384467291100. Its totient is φ = 5941598552064.

The previous prime is 25994534307829. The next prime is 25994534307943. The reversal of 25994534307840 is 4870343549952.

25994534307840 is a `hidden beast` number, since 2 + 5 + 9 + 94 + 5 + 3 + 430 + 78 + 40 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 25994335159296 + 199148544 = 5098464^2 + 14112^2 .

It is a tau number, because it is divible by the number of its divisors (720).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 40322766 + ... + 40962354.

Almost surely, 2^{25994534307840} is an apocalyptic number.

25994534307840 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 25994534307840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54192233645550).

25994534307840 is an abundant number, since it is smaller than the sum of its proper divisors (82389932983260).

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

25994534307840 is an equidigital number, since it uses as much as digits as its factorization.

25994534307840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 639642 (or 639606 counting only the distinct ones).

The product of its (nonzero) digits is 130636800, while the sum is 63.

The spelling of 25994534307840 in words is "twenty-five trillion, nine hundred ninety-four billion, five hundred thirty-four million, three hundred seven thousand, eight hundred forty".