20111697 has 12 divisors (see below), whose sum is σ = 30759300. Its totient is φ = 12619008.

The previous prime is 20111687. The next prime is 20111711. The reversal of 20111697 is 79611102.

It can be written as a sum of positive squares in 2 ways, for example, as 17564481 + 2547216 = 4191^2 + 1596^2 .

It is not a de Polignac number, because 20111697 - 2⁴ = 20111681 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20111697.

It is not an unprimeable number, because it can be changed into a prime (20111617) 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 11 ways as a sum of consecutive naturals, for example, 65572 + ... + 65877.

It is an arithmetic number, because the mean of its divisors is an integer number (2563275).

Almost surely, 2^20111697 is an apocalyptic number.

It is an amenable number.

20111697 is a deficient number, since it is larger than the sum of its proper divisors (10647603).

20111697 is a wasteful number, since it uses less digits than its factorization.

20111697 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131472 (or 131469 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 27.

The square root of 20111697 is about 4484.6066717160. The cubic root of 20111697 is about 271.9461443619.

Adding to 20111697 its reverse (79611102), we get a palindrome (99722799).

The spelling of 20111697 in words is "twenty million, one hundred eleven thousand, six hundred ninety-seven".