20409264171671 has 4 divisors (see below), whose sum is σ = 21483435970200. Its totient is φ = 19335092373144.

The previous prime is 20409264171587. The next prime is 20409264171689. The reversal of 20409264171671 is 17617146290402.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20409264171671 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20409264131671) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 537085899236 + ... + 537085899273.

It is an arithmetic number, because the mean of its divisors is an integer number (5370858992550).

Almost surely, 2^{20409264171671} is an apocalyptic number.

20409264171671 is a deficient number, since it is larger than the sum of its proper divisors (1074171798529).

20409264171671 is a wasteful number, since it uses less digits than its factorization.

20409264171671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1074171798528.

The product of its (nonzero) digits is 1016064, while the sum is 50.

The spelling of 20409264171671 in words is "twenty trillion, four hundred nine billion, two hundred sixty-four million, one hundred seventy-one thousand, six hundred seventy-one".