20117527531 has 4 divisors (see below), whose sum is σ = 20766480064. Its totient is φ = 19468575000.

The previous prime is 20117527519. The next prime is 20117527559. The reversal of 20117527531 is 13572571102.

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 20117527531 - 2⁵ = 20117527499 is a prime.

It is a super-2 number, since 2×20117527531² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20117527571) 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, 324476220 + ... + 324476281.

It is an arithmetic number, because the mean of its divisors is an integer number (5191620016).

Almost surely, 2^20117527531 is an apocalyptic number.

20117527531 is a deficient number, since it is larger than the sum of its proper divisors (648952533).

20117527531 is an equidigital number, since it uses as much as digits as its factorization.

20117527531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 648952532.

The product of its (nonzero) digits is 14700, while the sum is 34.

The spelling of 20117527531 in words is "twenty billion, one hundred seventeen million, five hundred twenty-seven thousand, five hundred thirty-one".