20432440 has 32 divisors (see below), whose sum is σ = 52541280. Its totient is φ = 7005312.

The previous prime is 20432437. The next prime is 20432449. The reversal of 20432440 is 4423402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20432449) 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, 36207 + ... + 36766.

It is an arithmetic number, because the mean of its divisors is an integer number (1641915).

Almost surely, 2^20432440 is an apocalyptic number.

20432440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20432440 is an abundant number, since it is smaller than the sum of its proper divisors (32108840).

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

20432440 is a wasteful number, since it uses less digits than its factorization.

20432440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72991 (or 72987 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 19.

The square root of 20432440 is about 4520.2256580839. The cubic root of 20432440 is about 273.3841996681.

Adding to 20432440 its reverse (4423402), we get a palindrome (24855842).

The spelling of 20432440 in words is "twenty million, four hundred thirty-two thousand, four hundred forty".