20136508471 has 4 divisors (see below), whose sum is σ = 20335879944. Its totient is φ = 19937137000.

The previous prime is 20136508429. The next prime is 20136508489. The reversal of 20136508471 is 17480563102.

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

It is a cyclic number.

It is not a de Polignac number, because 20136508471 - 2¹⁷ = 20136377399 is a prime.

It is a super-3 number, since 3×20136508471³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20136508471.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20136578471) 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, 99685585 + ... + 99685786.

It is an arithmetic number, because the mean of its divisors is an integer number (5083969986).

Almost surely, 2^20136508471 is an apocalyptic number.

20136508471 is a deficient number, since it is larger than the sum of its proper divisors (199371473).

20136508471 is a wasteful number, since it uses less digits than its factorization.

20136508471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199371472.

The product of its (nonzero) digits is 40320, while the sum is 37.

The spelling of 20136508471 in words is "twenty billion, one hundred thirty-six million, five hundred eight thousand, four hundred seventy-one".