25400784638 has 16 divisors (see below), whose sum is σ = 40158432720. Its totient is φ = 12016371456.

The previous prime is 25400784631. The next prime is 25400784671. The reversal of 25400784638 is 83648700452.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 25400784592 and 25400784601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25400784631) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 402995 + ... + 461742.

It is an arithmetic number, because the mean of its divisors is an integer number (2509902045).

Almost surely, 2^25400784638 is an apocalyptic number.

25400784638 is a deficient number, since it is larger than the sum of its proper divisors (14757648082).

25400784638 is a wasteful number, since it uses less digits than its factorization.

25400784638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 865531.

The product of its (nonzero) digits is 1290240, while the sum is 47.

The spelling of 25400784638 in words is "twenty-five billion, four hundred million, seven hundred eighty-four thousand, six hundred thirty-eight".