20475187 has 4 divisors (see below), whose sum is σ = 20721960. Its totient is φ = 20228416.

The previous prime is 20475167. The next prime is 20475197. The reversal of 20475187 is 78157402.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 20475187 - 2¹¹ = 20473139 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20475107) 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, 123262 + ... + 123427.

It is an arithmetic number, because the mean of its divisors is an integer number (5180490).

Almost surely, 2^20475187 is an apocalyptic number.

20475187 is a deficient number, since it is larger than the sum of its proper divisors (246773).

20475187 is an equidigital number, since it uses as much as digits as its factorization.

20475187 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246772.

The product of its (nonzero) digits is 15680, while the sum is 34.

The square root of 20475187 is about 4524.9516019511. The cubic root of 20475187 is about 273.5747172000.

The spelling of 20475187 in words is "twenty million, four hundred seventy-five thousand, one hundred eighty-seven".