25548178640 has 80 divisors (see below), whose sum is σ = 60198148560. Its totient is φ = 10082672640.

The previous prime is 25548178589. The next prime is 25548178651. The reversal of 25548178640 is 4687184552.

It can be written as a sum of positive squares in 8 ways, for example, as 372644416 + 25175534224 = 19304^2 + 158668^2 .

It is a tau number, because it is divible by the number of its divisors (80).

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, 2095442 + ... + 2107598.

It is an arithmetic number, because the mean of its divisors is an integer number (752476857).

Almost surely, 2^25548178640 is an apocalyptic number.

25548178640 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 25548178640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30099074280).

25548178640 is an abundant number, since it is smaller than the sum of its proper divisors (34649969920).

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

25548178640 is a wasteful number, since it uses less digits than its factorization.

25548178640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12520 (or 12514 counting only the distinct ones).

The product of its (nonzero) digits is 2150400, while the sum is 50.

The spelling of 25548178640 in words is "twenty-five billion, five hundred forty-eight million, one hundred seventy-eight thousand, six hundred forty".