20381245 has 8 divisors (see below), whose sum is σ = 24674616. Its totient is φ = 16160256.

The previous prime is 20381237. The next prime is 20381261. The reversal of 20381245 is 54218302.

It can be written as a sum of positive squares in 4 ways, for example, as 1205604 + 19175641 = 1098^2 + 4379^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20381245 - 2³ = 20381237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17472 + ... + 18601.

It is an arithmetic number, because the mean of its divisors is an integer number (3084327).

Almost surely, 2^20381245 is an apocalyptic number.

It is an amenable number.

20381245 is a deficient number, since it is larger than the sum of its proper divisors (4293371).

20381245 is a wasteful number, since it uses less digits than its factorization.

20381245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36191.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 20381245 is about 4514.5592254394. The cubic root of 20381245 is about 273.1556805476.

Adding to 20381245 its reverse (54218302), we get a palindrome (74599547).

The spelling of 20381245 in words is "twenty million, three hundred eighty-one thousand, two hundred forty-five".