20512173 has 16 divisors (see below), whose sum is σ = 30799872. Its totient is φ = 12030000.

The previous prime is 20512169. The next prime is 20512181. The reversal of 20512173 is 37121502.

It is not a de Polignac number, because 20512173 - 2² = 20512169 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20512073) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9003 + ... + 11048.

It is an arithmetic number, because the mean of its divisors is an integer number (1924992).

Almost surely, 2^20512173 is an apocalyptic number.

It is an amenable number.

20512173 is a deficient number, since it is larger than the sum of its proper divisors (10287699).

20512173 is a wasteful number, since it uses less digits than its factorization.

20512173 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20096.

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 20512173 is about 4529.0366525344. The cubic root of 20512173 is about 273.7393448867.

Adding to 20512173 its reverse (37121502), we get a palindrome (57633675).

It can be divided in two parts, 2051 and 2173, that added together give a palindrome (4224).

The spelling of 20512173 in words is "twenty million, five hundred twelve thousand, one hundred seventy-three".