20108387 has 4 divisors (see below), whose sum is σ = 21655200. Its totient is φ = 18561576.

The previous prime is 20108377. The next prime is 20108411. The reversal of 20108387 is 78380102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78380102 = 2 ⋅39190051.

It is a cyclic number.

It is not a de Polignac number, because 20108387 - 2¹⁰ = 20107363 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20108357) 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, 773387 + ... + 773412.

It is an arithmetic number, because the mean of its divisors is an integer number (5413800).

Almost surely, 2^20108387 is an apocalyptic number.

20108387 is a deficient number, since it is larger than the sum of its proper divisors (1546813).

20108387 is a wasteful number, since it uses less digits than its factorization.

20108387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1546812.

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 20108387 is about 4484.2376163625. The cubic root of 20108387 is about 271.9312245016.

Adding to 20108387 its reverse (78380102), we get a palindrome (98488489).

The spelling of 20108387 in words is "twenty million, one hundred eight thousand, three hundred eighty-seven".