20015140 has 24 divisors (see below), whose sum is σ = 42610680. Its totient is φ = 7895808.

The previous prime is 20015131. The next prime is 20015143. The reversal of 20015140 is 4151002.

It can be written as a sum of positive squares in 4 ways, for example, as 5635876 + 14379264 = 2374^2 + 3792^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20015140.

It is not an unprimeable number, because it can be changed into a prime (20015143) 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, 5395 + ... + 8314.

It is an arithmetic number, because the mean of its divisors is an integer number (1775445).

Almost surely, 2^20015140 is an apocalyptic number.

20015140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20015140 is an abundant number, since it is smaller than the sum of its proper divisors (22595540).

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

20015140 is a wasteful number, since it uses less digits than its factorization.

20015140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13791 (or 13789 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 13.

The square root of 20015140 is about 4473.8283382356. The cubic root of 20015140 is about 271.5102381880.

Adding to 20015140 its reverse (4151002), we get a palindrome (24166142).

The spelling of 20015140 in words is "twenty million, fifteen thousand, one hundred forty".