20553679 has 4 divisors (see below), whose sum is σ = 20620080. Its totient is φ = 20487280.

The previous prime is 20553647. The next prime is 20553691. The reversal of 20553679 is 97635502.

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 20553679 - 2⁵ = 20553647 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 (20553619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32734 + ... + 33355.

It is an arithmetic number, because the mean of its divisors is an integer number (5155020).

Almost surely, 2^20553679 is an apocalyptic number.

20553679 is a deficient number, since it is larger than the sum of its proper divisors (66401).

20553679 is an equidigital number, since it uses as much as digits as its factorization.

20553679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66400.

The product of its (nonzero) digits is 56700, while the sum is 37.

The square root of 20553679 is about 4533.6165475258. The cubic root of 20553679 is about 273.9238559795.

The spelling of 20553679 in words is "twenty million, five hundred fifty-three thousand, six hundred seventy-nine".