20172072 has 64 divisors (see below), whose sum is σ = 54835200. Its totient is φ = 6160320.

The previous prime is 20172037. The next prime is 20172073. The reversal of 20172072 is 27027102.

It is not an unprimeable number, because it can be changed into a prime (20172073) 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, 13423 + ... + 14849.

It is an arithmetic number, because the mean of its divisors is an integer number (856800).

Almost surely, 2^20172072 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 20172072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27417600).

20172072 is an abundant number, since it is smaller than the sum of its proper divisors (34663128).

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

20172072 is a wasteful number, since it uses less digits than its factorization.

20172072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1486 (or 1482 counting only the distinct ones).

The product of its (nonzero) digits is 392, while the sum is 21.

The square root of 20172072 is about 4491.3329869873. The cubic root of 20172072 is about 272.2179985338.

Adding to 20172072 its reverse (27027102), we get a palindrome (47199174).

The spelling of 20172072 in words is "twenty million, one hundred seventy-two thousand, seventy-two".