20431572 has 24 divisors (see below), whose sum is σ = 54484416. Its totient is φ = 5837568.

The previous prime is 20431549. The next prime is 20431577. The reversal of 20431572 is 27513402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20431577) 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 7 ways as a sum of consecutive naturals, for example, 121533 + ... + 121700.

It is an arithmetic number, because the mean of its divisors is an integer number (2270184).

Almost surely, 2^20431572 is an apocalyptic number.

It is an amenable number.

20431572 is an abundant number, since it is smaller than the sum of its proper divisors (34052844).

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

20431572 is a wasteful number, since it uses less digits than its factorization.

20431572 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 243247 (or 243245 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 24.

The square root of 20431572 is about 4520.1296441585. The cubic root of 20431572 is about 273.3803283595.

Adding to 20431572 its reverse (27513402), we get a palindrome (47944974).

The spelling of 20431572 in words is "twenty million, four hundred thirty-one thousand, five hundred seventy-two".