20208040 has 16 divisors (see below), whose sum is σ = 45468180. Its totient is φ = 8083200.

The previous prime is 20208029. The next prime is 20208043. The reversal of 20208040 is 4080202.

It can be written as a sum of positive squares in 2 ways, for example, as 20088324 + 119716 = 4482^2 + 346^2 .

It is not an unprimeable number, because it can be changed into a prime (20208043) 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 3 ways as a sum of consecutive naturals, for example, 252561 + ... + 252640.

Almost surely, 2^20208040 is an apocalyptic number.

20208040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20208040 is an abundant number, since it is smaller than the sum of its proper divisors (25260140).

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

20208040 is a wasteful number, since it uses less digits than its factorization.

20208040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 505212 (or 505208 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 20208040 is about 4495.3353601261. The cubic root of 20208040 is about 272.3796960751.

Adding to 20208040 its reverse (4080202), we get a palindrome (24288242).

The spelling of 20208040 in words is "twenty million, two hundred eight thousand, forty".