25641546840 has 512 divisors, whose sum is σ = 106009344000. Its totient is φ = 5368301568.

The previous prime is 25641546787. The next prime is 25641546877. The reversal of 25641546840 is 4864514652.

It is a happy number.

25641546840 is a `hidden beast` number, since 2 + 5 + 64 + 1 + 546 + 8 + 40 = 666.

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 pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 13659982 + ... + 13661858.

It is an arithmetic number, because the mean of its divisors is an integer number (207049500).

Almost surely, 2^25641546840 is an apocalyptic number.

25641546840 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 25641546840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53004672000).

25641546840 is an abundant number, since it is smaller than the sum of its proper divisors (80367797160).

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

25641546840 is a wasteful number, since it uses less digits than its factorization.

25641546840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2056 (or 2046 counting only the distinct ones).

The product of its (nonzero) digits is 921600, while the sum is 45.

The spelling of 25641546840 in words is "twenty-five billion, six hundred forty-one million, five hundred forty-six thousand, eight hundred forty".