20791679 has 4 divisors (see below), whose sum is σ = 20804784. Its totient is φ = 20778576.

The previous prime is 20791657. The next prime is 20791691. The reversal of 20791679 is 97619702.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20791679 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 (20791649) 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, 3782 + ... + 7475.

It is an arithmetic number, because the mean of its divisors is an integer number (5201196).

Almost surely, 2^20791679 is an apocalyptic number.

20791679 is a deficient number, since it is larger than the sum of its proper divisors (13105).

20791679 is a wasteful number, since it uses less digits than its factorization.

20791679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13104.

The product of its (nonzero) digits is 47628, while the sum is 41.

The square root of 20791679 is about 4559.7893591700. The cubic root of 20791679 is about 274.9770956130.

The spelling of 20791679 in words is "twenty million, seven hundred ninety-one thousand, six hundred seventy-nine".