20381851 has 8 divisors (see below), whose sum is σ = 24519680. Its totient is φ = 16550568.

The previous prime is 20381843. The next prime is 20381891. The reversal of 20381851 is 15818302.

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 20381851 - 2³ = 20381843 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20381821) 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 7 ways as a sum of consecutive naturals, for example, 76491 + ... + 76756.

It is an arithmetic number, because the mean of its divisors is an integer number (3064960).

Almost surely, 2^20381851 is an apocalyptic number.

20381851 is a deficient number, since it is larger than the sum of its proper divisors (4137829).

20381851 is a wasteful number, since it uses less digits than its factorization.

20381851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153273.

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 20381851 is about 4514.6263411272. The cubic root of 20381851 is about 273.1583877865.

The spelling of 20381851 in words is "twenty million, three hundred eighty-one thousand, eight hundred fifty-one".