20140440 has 64 divisors (see below), whose sum is σ = 61724160. Its totient is φ = 5255040.

The previous prime is 20140429. The next prime is 20140451. The reversal of 20140440 is 4404102.

It is an interprime number because it is at equal distance from previous prime (20140429) and next prime (20140451).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 3855 + ... + 7425.

It is an arithmetic number, because the mean of its divisors is an integer number (964440).

Almost surely, 2^20140440 is an apocalyptic number.

20140440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20140440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30862080).

20140440 is an abundant number, since it is smaller than the sum of its proper divisors (41583720).

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

20140440 is a wasteful number, since it uses less digits than its factorization.

20140440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3632 (or 3628 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 15.

The square root of 20140440 is about 4487.8101564126. The cubic root of 20140440 is about 272.0756349640.

Adding to 20140440 its reverse (4404102), we get a palindrome (24544542).

The spelling of 20140440 in words is "twenty million, one hundred forty thousand, four hundred forty".