25405040 has 20 divisors (see below), whose sum is σ = 59066904. Its totient is φ = 10161984.

The previous prime is 25405019. The next prime is 25405043. The reversal of 25405040 is 4050452.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25405043) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 158702 + ... + 158861.

Almost surely, 2^25405040 is an apocalyptic number.

25405040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25405040 is an abundant number, since it is smaller than the sum of its proper divisors (33661864).

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

25405040 is a wasteful number, since it uses less digits than its factorization.

25405040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317576 (or 317570 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 20.

The square root of 25405040 is about 5040.3412582880. The cubic root of 25405040 is about 293.9724471688.

Adding to 25405040 its reverse (4050452), we get a palindrome (29455492).

The spelling of 25405040 in words is "twenty-five million, four hundred five thousand, forty".