25638463939487 has 8 divisors (see below), whose sum is σ = 29514978300576. Its totient is φ = 21815418742272.

The previous prime is 25638463939481. The next prime is 25638463939547. The reversal of 25638463939487 is 78493936483652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 25638463939487 - 2¹⁶ = 25638463873951 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25638463939481) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13367289938 + ... + 13367291855.

It is an arithmetic number, because the mean of its divisors is an integer number (3689372287572).

Almost surely, 2^{25638463939487} is an apocalyptic number.

25638463939487 is a deficient number, since it is larger than the sum of its proper divisors (3876514361089).

25638463939487 is a wasteful number, since it uses less digits than its factorization.

25638463939487 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26734581937.

The product of its digits is 5643509760, while the sum is 77.

The spelling of 25638463939487 in words is "twenty-five trillion, six hundred thirty-eight billion, four hundred sixty-three million, nine hundred thirty-nine thousand, four hundred eighty-seven".