20873992947 has 4 divisors (see below), whose sum is σ = 27831990600. Its totient is φ = 13915995296.

The previous prime is 20873992889. The next prime is 20873992949. The reversal of 20873992947 is 74929937802.

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 20873992947 - 2¹⁵ = 20873960179 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20873992949) 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, 3478998822 + ... + 3478998827.

It is an arithmetic number, because the mean of its divisors is an integer number (6957997650).

Almost surely, 2^20873992947 is an apocalyptic number.

20873992947 is a deficient number, since it is larger than the sum of its proper divisors (6957997653).

20873992947 is an equidigital number, since it uses as much as digits as its factorization.

20873992947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6957997652.

The product of its (nonzero) digits is 13716864, while the sum is 60.

The spelling of 20873992947 in words is "twenty billion, eight hundred seventy-three million, nine hundred ninety-two thousand, nine hundred forty-seven".