25440140 has 24 divisors (see below), whose sum is σ = 58281552. Its totient is φ = 9250880.

The previous prime is 25440091. The next prime is 25440167. The reversal of 25440140 is 4104452.

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

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 7 ways as a sum of consecutive naturals, for example, 57599 + ... + 58038.

It is an arithmetic number, because the mean of its divisors is an integer number (2428398).

Almost surely, 2^25440140 is an apocalyptic number.

25440140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25440140 is an abundant number, since it is smaller than the sum of its proper divisors (32841412).

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

25440140 is a wasteful number, since it uses less digits than its factorization.

25440140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115657 (or 115655 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 25440140 is about 5043.8219635511. The cubic root of 25440140 is about 294.1077705076.

Adding to 25440140 its reverse (4104452), we get a palindrome (29544592).

The spelling of 25440140 in words is "twenty-five million, four hundred forty thousand, one hundred forty".