20713811 has 4 divisors (see below), whose sum is σ = 20724312. Its totient is φ = 20703312.

The previous prime is 20713799. The next prime is 20713829. The reversal of 20713811 is 11831702.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 11831702 = 2 ⋅5915851.

It is a cyclic number.

It is not a de Polignac number, because 20713811 - 2²² = 16519507 is a prime.

It is a super-2 number, since 2×20713811² = 858123932287442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20713411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1301 + ... + 6566.

It is an arithmetic number, because the mean of its divisors is an integer number (5181078).

Almost surely, 2^20713811 is an apocalyptic number.

20713811 is a deficient number, since it is larger than the sum of its proper divisors (10501).

20713811 is an equidigital number, since it uses as much as digits as its factorization.

20713811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10500.

The product of its (nonzero) digits is 336, while the sum is 23.

The square root of 20713811 is about 4551.2427973027. The cubic root of 20713811 is about 274.6333891631.

The spelling of 20713811 in words is "twenty million, seven hundred thirteen thousand, eight hundred eleven".