20051172 has 96 divisors (see below), whose sum is σ = 55157760. Its totient is φ = 6289920.

The previous prime is 20051159. The next prime is 20051179. The reversal of 20051172 is 27115002.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (20051179) 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 31 ways as a sum of consecutive naturals, for example, 177388 + ... + 177500.

It is an arithmetic number, because the mean of its divisors is an integer number (574560).

Almost surely, 2^20051172 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20051172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27578880).

20051172 is an abundant number, since it is smaller than the sum of its proper divisors (35106588).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20051172 is a wasteful number, since it uses less digits than its factorization.

20051172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210 (or 202 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 18.

The square root of 20051172 is about 4477.8535036332. The cubic root of 20051172 is about 271.6730681284.

Adding to 20051172 its reverse (27115002), we get a palindrome (47166174).

The spelling of 20051172 in words is "twenty million, fifty-one thousand, one hundred seventy-two".