20992047 has 4 divisors (see below), whose sum is σ = 27989400. Its totient is φ = 13994696.

The previous prime is 20992039. The next prime is 20992051. The reversal of 20992047 is 74029902.

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 20992047 - 2³ = 20992039 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20991999 and 20992017.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20992007) 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, 3498672 + ... + 3498677.

It is an arithmetic number, because the mean of its divisors is an integer number (6997350).

Almost surely, 2^20992047 is an apocalyptic number.

20992047 is a deficient number, since it is larger than the sum of its proper divisors (6997353).

20992047 is an equidigital number, since it uses as much as digits as its factorization.

20992047 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6997352.

The product of its (nonzero) digits is 9072, while the sum is 33.

The square root of 20992047 is about 4581.7078693430. The cubic root of 20992047 is about 275.8575851073.

The spelling of 20992047 in words is "twenty million, nine hundred ninety-two thousand, forty-seven".