20143240 has 32 divisors (see below), whose sum is σ = 48809880. Its totient is φ = 7437312.

The previous prime is 20143231. The next prime is 20143241. The reversal of 20143240 is 4234102.

It can be written as a sum of positive squares in 4 ways, for example, as 7851204 + 12292036 = 2802^2 + 3506^2 .

It is not an unprimeable number, because it can be changed into a prime (20143241) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 18849 + ... + 19888.

Almost surely, 2^20143240 is an apocalyptic number.

20143240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20143240 is an abundant number, since it is smaller than the sum of its proper divisors (28666640).

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

20143240 is a wasteful number, since it uses less digits than its factorization.

20143240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38761 (or 38757 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 20143240 is about 4488.1221017258. The cubic root of 20143240 is about 272.0882427070.

Adding to 20143240 its reverse (4234102), we get a palindrome (24377342).

The spelling of 20143240 in words is "twenty million, one hundred forty-three thousand, two hundred forty".