20111709 has 8 divisors (see below), whose sum is σ = 28227040. Its totient is φ = 12702096.

The previous prime is 20111687. The next prime is 20111711. The reversal of 20111709 is 90711102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20111709 - 2¹⁵ = 20078941 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 (20111789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 176362 + ... + 176475.

It is an arithmetic number, because the mean of its divisors is an integer number (3528380).

Almost surely, 2^20111709 is an apocalyptic number.

It is an amenable number.

20111709 is a deficient number, since it is larger than the sum of its proper divisors (8115331).

20111709 is a wasteful number, since it uses less digits than its factorization.

20111709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 352859.

The product of its (nonzero) digits is 126, while the sum is 21.

The square root of 20111709 is about 4484.6080096258. The cubic root of 20111709 is about 271.9461984490.

The spelling of 20111709 in words is "twenty million, one hundred eleven thousand, seven hundred nine".