20045240 has 16 divisors (see below), whose sum is σ = 45101880. Its totient is φ = 8018080.

The previous prime is 20045237. The next prime is 20045243. The reversal of 20045240 is 4254002.

It is an interprime number because it is at equal distance from previous prime (20045237) and next prime (20045243).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20045243) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 250526 + ... + 250605.

Almost surely, 2^20045240 is an apocalyptic number.

20045240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20045240 is an abundant number, since it is smaller than the sum of its proper divisors (25056640).

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

20045240 is a wasteful number, since it uses less digits than its factorization.

20045240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 501142 (or 501138 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 17.

The square root of 20045240 is about 4477.1910837042. The cubic root of 20045240 is about 271.6462746224.

Adding to 20045240 its reverse (4254002), we get a palindrome (24299242).

The spelling of 20045240 in words is "twenty million, forty-five thousand, two hundred forty".