20178878987 has 8 divisors (see below), whose sum is σ = 20303798304. Its totient is φ = 20054055168.

The previous prime is 20178878969. The next prime is 20178878999. The reversal of 20178878987 is 78987887102.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20178878987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20178878947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 426098 + ... + 471080.

It is an arithmetic number, because the mean of its divisors is an integer number (2537974788).

Almost surely, 2^20178878987 is an apocalyptic number.

20178878987 is a deficient number, since it is larger than the sum of its proper divisors (124919317).

20178878987 is a wasteful number, since it uses less digits than its factorization.

20178878987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47749.

The product of its (nonzero) digits is 25288704, while the sum is 65.

The spelling of 20178878987 in words is "twenty billion, one hundred seventy-eight million, eight hundred seventy-eight thousand, nine hundred eighty-seven".