20813679 has 32 divisors (see below), whose sum is σ = 32327680. Its totient is φ = 13384440.

The previous prime is 20813669. The next prime is 20813693. The reversal of 20813679 is 97631802.

It is not a de Polignac number, because 20813679 - 2¹² = 20809583 is a prime.

It is a Duffinian number.

It is a zygodrome in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20813669) 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 31 ways as a sum of consecutive naturals, for example, 67644 + ... + 67950.

It is an arithmetic number, because the mean of its divisors is an integer number (1010240).

Almost surely, 2^20813679 is an apocalyptic number.

20813679 is a deficient number, since it is larger than the sum of its proper divisors (11514001).

20813679 is an frugal number, since it uses more digits than its factorization.

20813679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 359 (or 341 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 20813679 is about 4562.2011134977. The cubic root of 20813679 is about 275.0740472777.

The spelling of 20813679 in words is "twenty million, eight hundred thirteen thousand, six hundred seventy-nine".