20731272 has 16 divisors (see below), whose sum is σ = 51828240. Its totient is φ = 6910416.

The previous prime is 20731267. The next prime is 20731273. The reversal of 20731272 is 27213702.

It is a Harshad number since it is a multiple of its sum of digits (24), and also a Moran number because the ratio is a prime number: 863803 = 20731272 / (2 + 0 + 7 + 3 + 1 + 2 + 7 + 2).

It is not an unprimeable number, because it can be changed into a prime (20731273) 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 in 3 ways as a sum of consecutive naturals, for example, 431878 + ... + 431925.

It is an arithmetic number, because the mean of its divisors is an integer number (3239265).

Almost surely, 2^20731272 is an apocalyptic number.

It is an amenable number.

20731272 is an abundant number, since it is smaller than the sum of its proper divisors (31096968).

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

20731272 is a wasteful number, since it uses less digits than its factorization.

20731272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 863812 (or 863808 counting only the distinct ones).

The product of its (nonzero) digits is 1176, while the sum is 24.

The square root of 20731272 is about 4553.1606604643. The cubic root of 20731272 is about 274.7105361899.

Adding to 20731272 its reverse (27213702), we get a palindrome (47944974).

The spelling of 20731272 in words is "twenty million, seven hundred thirty-one thousand, two hundred seventy-two".