20172672 has 128 divisors (see below), whose sum is σ = 64260000. Its totient is φ = 6193152.

The previous prime is 20172667. The next prime is 20172683. The reversal of 20172672 is 27627102.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44704 + ... + 45152.

Almost surely, 2^20172672 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 20172672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32130000).

20172672 is an abundant number, since it is smaller than the sum of its proper divisors (44087328).

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

20172672 is a wasteful number, since it uses less digits than its factorization.

20172672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 485 (or 467 counting only the distinct ones).

The product of its (nonzero) digits is 2352, while the sum is 27.

The square root of 20172672 is about 4491.3997818052. The cubic root of 20172672 is about 272.2206974663.

Adding to 20172672 its reverse (27627102), we get a palindrome (47799774).

The spelling of 20172672 in words is "twenty million, one hundred seventy-two thousand, six hundred seventy-two".