20123711 has 4 divisors (see below), whose sum is σ = 20178912. Its totient is φ = 20068512.

The previous prime is 20123707. The next prime is 20123713. The reversal of 20123711 is 11732102.

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 20123711 - 2² = 20123707 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20123711.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20123713) 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, 27050 + ... + 27783.

It is an arithmetic number, because the mean of its divisors is an integer number (5044728).

Almost surely, 2^20123711 is an apocalyptic number.

20123711 is a deficient number, since it is larger than the sum of its proper divisors (55201).

20123711 is an equidigital number, since it uses as much as digits as its factorization.

20123711 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55200.

The product of its (nonzero) digits is 84, while the sum is 17.

The square root of 20123711 is about 4485.9459426079. The cubic root of 20123711 is about 272.0002838449. Note that the first 3 decimals are identical.

Adding to 20123711 its reverse (11732102), we get a palindrome (31855813).

The spelling of 20123711 in words is "twenty million, one hundred twenty-three thousand, seven hundred eleven".