20381117 has 4 divisors (see below), whose sum is σ = 20931996. Its totient is φ = 19830240.

The previous prime is 20381107. The next prime is 20381149. The reversal of 20381117 is 71118302.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15912121 + 4468996 = 3989^2 + 2114^2 .

It is a cyclic number.

It is not a de Polignac number, because 20381117 - 2²⁰ = 19332541 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20381092 and 20381101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20381107) 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, 275384 + ... + 275457.

It is an arithmetic number, because the mean of its divisors is an integer number (5232999).

Almost surely, 2^20381117 is an apocalyptic number.

It is an amenable number.

20381117 is a deficient number, since it is larger than the sum of its proper divisors (550879).

20381117 is an equidigital number, since it uses as much as digits as its factorization.

20381117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 550878.

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

The square root of 20381117 is about 4514.5450490609. The cubic root of 20381117 is about 273.1551087146.

Adding to 20381117 its reverse (71118302), we get a palindrome (91499419).

The spelling of 20381117 in words is "twenty million, three hundred eighty-one thousand, one hundred seventeen".