20185240 has 16 divisors (see below), whose sum is σ = 45416880. Its totient is φ = 8074080.

The previous prime is 20185213. The next prime is 20185241. The reversal of 20185240 is 4258102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20185241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 252276 + ... + 252355.

It is an arithmetic number, because the mean of its divisors is an integer number (2838555).

Almost surely, 2^20185240 is an apocalyptic number.

20185240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20185240 is an abundant number, since it is smaller than the sum of its proper divisors (25231640).

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

20185240 is a wasteful number, since it uses less digits than its factorization.

20185240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 504642 (or 504638 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 20185240 is about 4492.7986823360. The cubic root of 20185240 is about 272.2772188080.

The spelling of 20185240 in words is "twenty million, one hundred eighty-five thousand, two hundred forty".