20540197 has 16 divisors (see below), whose sum is σ = 22865920. Its totient is φ = 18370800.

The previous prime is 20540171. The next prime is 20540209. The reversal of 20540197 is 79104502.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20540197 - 2¹⁵ = 20507429 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 (20540137) 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 15 ways as a sum of consecutive naturals, for example, 24922 + ... + 25732.

It is an arithmetic number, because the mean of its divisors is an integer number (1429120).

Almost surely, 2^20540197 is an apocalyptic number.

It is an amenable number.

20540197 is a deficient number, since it is larger than the sum of its proper divisors (2325723).

20540197 is a wasteful number, since it uses less digits than its factorization.

20540197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 904.

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 20540197 is about 4532.1294112150. The cubic root of 20540197 is about 273.8639502534.

Adding to 20540197 its reverse (79104502), we get a palindrome (99644699).

The spelling of 20540197 in words is "twenty million, five hundred forty thousand, one hundred ninety-seven".