20180440 has 32 divisors (see below), whose sum is σ = 51893280. Its totient is φ = 6918912.

The previous prime is 20180399. The next prime is 20180441. The reversal of 20180440 is 4408102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20180441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35757 + ... + 36316.

It is an arithmetic number, because the mean of its divisors is an integer number (1621665).

Almost surely, 2^20180440 is an apocalyptic number.

20180440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20180440 is an abundant number, since it is smaller than the sum of its proper divisors (31712840).

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

20180440 is a wasteful number, since it uses less digits than its factorization.

20180440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72091 (or 72087 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 20180440 is about 4492.2644623842. The cubic root of 20180440 is about 272.2556348146.

Adding to 20180440 its reverse (4408102), we get a palindrome (24588542).

The spelling of 20180440 in words is "twenty million, one hundred eighty thousand, four hundred forty".