20378705 has 4 divisors (see below), whose sum is σ = 24454452. Its totient is φ = 16302960.

The previous prime is 20378663. The next prime is 20378707. The reversal of 20378705 is 50787302.

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 6599761 + 13778944 = 2569^2 + 3712^2 .

It is not a de Polignac number, because 20378705 - 2¹⁰ = 20377681 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20378707) 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 3 ways as a sum of consecutive naturals, for example, 2037866 + ... + 2037875.

It is an arithmetic number, because the mean of its divisors is an integer number (6113613).

Almost surely, 2^20378705 is an apocalyptic number.

It is an amenable number.

20378705 is a deficient number, since it is larger than the sum of its proper divisors (4075747).

20378705 is an equidigital number, since it uses as much as digits as its factorization.

20378705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4075746.

The product of its (nonzero) digits is 11760, while the sum is 32.

The square root of 20378705 is about 4514.2779046045. The cubic root of 20378705 is about 273.1443327905.

The spelling of 20378705 in words is "twenty million, three hundred seventy-eight thousand, seven hundred five".