20818079 has 4 divisors (see below), whose sum is σ = 21052080. Its totient is φ = 20584080.

The previous prime is 20818073. The next prime is 20818099. The reversal of 20818079 is 97081802.

It is a happy number.

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 20818079 - 2¹² = 20813983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20818073) 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, 116867 + ... + 117044.

It is an arithmetic number, because the mean of its divisors is an integer number (5263020).

Almost surely, 2^20818079 is an apocalyptic number.

20818079 is a deficient number, since it is larger than the sum of its proper divisors (234001).

20818079 is an equidigital number, since it uses as much as digits as its factorization.

20818079 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234000.

The product of its (nonzero) digits is 8064, while the sum is 35.

The square root of 20818079 is about 4562.6833113860. The cubic root of 20818079 is about 275.0934294114.

The spelling of 20818079 in words is "twenty million, eight hundred eighteen thousand, seventy-nine".