20188661517 has 12 divisors (see below), whose sum is σ = 29200657824. Its totient is φ = 13440988680.

The previous prime is 20188661461. The next prime is 20188661587. The reversal of 20188661517 is 71516688102.

20188661517 is a `hidden beast` number, since 2 + 0 + 18 + 8 + 6 + 615 + 17 = 666.

It is not a de Polignac number, because 20188661517 - 2¹⁰ = 20188660493 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20188661587) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1502859 + ... + 1516232.

It is an arithmetic number, because the mean of its divisors is an integer number (2433388152).

Almost surely, 2^20188661517 is an apocalyptic number.

It is an amenable number.

20188661517 is a deficient number, since it is larger than the sum of its proper divisors (9011996307).

20188661517 is a wasteful number, since it uses less digits than its factorization.

20188661517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3019840 (or 3019837 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 45.

The spelling of 20188661517 in words is "twenty billion, one hundred eighty-eight million, six hundred sixty-one thousand, five hundred seventeen".