20508971 has 8 divisors (see below), whose sum is σ = 23595264. Its totient is φ = 17461800.

The previous prime is 20508941. The next prime is 20508991. The reversal of 20508971 is 17980502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20508971 - 2⁶ = 20508907 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20508911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8645 + ... + 10758.

It is an arithmetic number, because the mean of its divisors is an integer number (2949408).

Almost surely, 2^20508971 is an apocalyptic number.

20508971 is a deficient number, since it is larger than the sum of its proper divisors (3086293).

20508971 is a wasteful number, since it uses less digits than its factorization.

20508971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19561.

The product of its (nonzero) digits is 5040, while the sum is 32.

The square root of 20508971 is about 4528.6831419299. The cubic root of 20508971 is about 273.7251003534.

The spelling of 20508971 in words is "twenty million, five hundred eight thousand, nine hundred seventy-one".