20615502171 has 12 divisors (see below), whose sum is σ = 30213353576. Its totient is φ = 12494243520.

The previous prime is 20615502157. The next prime is 20615502181. The reversal of 20615502171 is 17120551602.

It is not a de Polignac number, because 20615502171 - 2⁹ = 20615501659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20615502181) 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 11 ways as a sum of consecutive naturals, for example, 28395646 + ... + 28396371.

Almost surely, 2^20615502171 is an apocalyptic number.

20615502171 is a deficient number, since it is larger than the sum of its proper divisors (9597851405).

20615502171 is a wasteful number, since it uses less digits than its factorization.

20615502171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56792042 (or 56792031 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 30.

The spelling of 20615502171 in words is "twenty billion, six hundred fifteen million, five hundred two thousand, one hundred seventy-one".