20987207177 has 8 divisors (see below), whose sum is σ = 21143968512. Its totient is φ = 20830680000.

The previous prime is 20987207077. The next prime is 20987207191. The reversal of 20987207177 is 77170278902.

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 20987207177 - 2⁸ = 20987206921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20987207077) 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, 123488 + ... + 239214.

It is an arithmetic number, because the mean of its divisors is an integer number (2642996064).

Almost surely, 2^20987207177 is an apocalyptic number.

It is an amenable number.

20987207177 is a deficient number, since it is larger than the sum of its proper divisors (156761335).

20987207177 is a wasteful number, since it uses less digits than its factorization.

20987207177 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117079.

The product of its (nonzero) digits is 691488, while the sum is 50.

The spelling of 20987207177 in words is "twenty billion, nine hundred eighty-seven million, two hundred seven thousand, one hundred seventy-seven".