20820884861 has 8 divisors (see below), whose sum is σ = 25195020480. Its totient is φ = 16796680128.

The previous prime is 20820884837. The next prime is 20820884867. The reversal of 20820884861 is 16848802802.

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 20820884861 - 2³⁰ = 19747143037 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20820884867) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 87482591 + ... + 87482828.

It is an arithmetic number, because the mean of its divisors is an integer number (3149377560).

Almost surely, 2^20820884861 is an apocalyptic number.

It is an amenable number.

20820884861 is a deficient number, since it is larger than the sum of its proper divisors (4374135619).

20820884861 is a wasteful number, since it uses less digits than its factorization.

20820884861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174965443.

The product of its (nonzero) digits is 393216, while the sum is 47.

The spelling of 20820884861 in words is "twenty billion, eight hundred twenty million, eight hundred eighty-four thousand, eight hundred sixty-one".