20172874 has 4 divisors (see below), whose sum is σ = 30259314. Its totient is φ = 10086436.

The previous prime is 20172827. The next prime is 20172877. The reversal of 20172874 is 47827102.

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

It can be written as a sum of positive squares in only one way, i.e., 19864849 + 308025 = 4457^2 + 555^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (20172877) 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 as a sum of consecutive naturals, namely, 5043217 + ... + 5043220.

Almost surely, 2^20172874 is an apocalyptic number.

20172874 is a deficient number, since it is larger than the sum of its proper divisors (10086440).

20172874 is a wasteful number, since it uses less digits than its factorization.

20172874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10086439.

The product of its (nonzero) digits is 6272, while the sum is 31.

The square root of 20172874 is about 4491.4222691704. The cubic root of 20172874 is about 272.2216060948.

Adding to 20172874 its reverse (47827102), we get a palindrome (67999976).

The spelling of 20172874 in words is "twenty million, one hundred seventy-two thousand, eight hundred seventy-four".