25405680 has 80 divisors (see below), whose sum is σ = 80914464. Its totient is φ = 6589440.

The previous prime is 25405661. The next prime is 25405693. The reversal of 25405680 is 8650452.

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

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7450 + ... + 10310.

Almost surely, 2^25405680 is an apocalyptic number.

25405680 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 25405680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40457232).

25405680 is an abundant number, since it is smaller than the sum of its proper divisors (55508784).

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

25405680 is a wasteful number, since it uses less digits than its factorization.

25405680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2914 (or 2908 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 30.

The square root of 25405680 is about 5040.4047456529. The cubic root of 25405680 is about 293.9749157182.

The spelling of 25405680 in words is "twenty-five million, four hundred five thousand, six hundred eighty".