25517606987 has 8 divisors (see below), whose sum is σ = 25651777536. Its totient is φ = 25383768552.

The previous prime is 25517606981. The next prime is 25517607041. The reversal of 25517606987 is 78960671552.

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 25517606987 - 2⁶ = 25517606923 is a prime.

It is a super-2 number, since 2×25517606987² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25517606981) 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, 71798 + ... + 237044.

It is an arithmetic number, because the mean of its divisors is an integer number (3206472192).

Almost surely, 2^25517606987 is an apocalyptic number.

25517606987 is a deficient number, since it is larger than the sum of its proper divisors (134170549).

25517606987 is a wasteful number, since it uses less digits than its factorization.

25517606987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166057.

The product of its (nonzero) digits is 6350400, while the sum is 56.

The spelling of 25517606987 in words is "twenty-five billion, five hundred seventeen million, six hundred six thousand, nine hundred eighty-seven".