20722111 has 4 divisors (see below), whose sum is σ = 20744424. Its totient is φ = 20699800.

The previous prime is 20722073. The next prime is 20722123. The reversal of 20722111 is 11122702.

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 20722111 - 2⁷ = 20721983 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 (20722171) 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, 9700 + ... + 11641.

It is an arithmetic number, because the mean of its divisors is an integer number (5186106).

Almost surely, 2^20722111 is an apocalyptic number.

20722111 is a deficient number, since it is larger than the sum of its proper divisors (22313).

20722111 is an equidigital number, since it uses as much as digits as its factorization.

20722111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22312.

The product of its (nonzero) digits is 56, while the sum is 16.

The square root of 20722111 is about 4552.1545448282. The cubic root of 20722111 is about 274.6700660247.

Adding to 20722111 its reverse (11122702), we get a palindrome (31844813).

The spelling of 20722111 in words is "twenty million, seven hundred twenty-two thousand, one hundred eleven".