20172432 has 40 divisors (see below), whose sum is σ = 59557696. Its totient is φ = 5763456.

The previous prime is 20172419. The next prime is 20172443. The reversal of 20172432 is 23427102.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 20172399 and 20172408.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29683 + ... + 30354.

Almost surely, 2^20172432 is an apocalyptic number.

It is an amenable number.

20172432 is an abundant number, since it is smaller than the sum of its proper divisors (39385264).

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

20172432 is a wasteful number, since it uses less digits than its factorization.

20172432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60055 (or 60049 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 21.

The square root of 20172432 is about 4491.3730639972. The cubic root of 20172432 is about 272.2196178997.

Adding to 20172432 its reverse (23427102), we get a palindrome (43599534).

It can be divided in two parts, 20172 and 432, that multiplied together give a square (8714304 = 2952²).

The spelling of 20172432 in words is "twenty million, one hundred seventy-two thousand, four hundred thirty-two".