20530240 has 28 divisors (see below), whose sum is σ = 48888396. Its totient is φ = 8211968.

The previous prime is 20530229. The next prime is 20530247. The reversal of 20530240 is 4203502.

It can be written as a sum of positive squares in 2 ways, for example, as 14017536 + 6512704 = 3744^2 + 2552^2 .

It is a Harshad number since it is a multiple of its sum of digits (16).

It is not an unprimeable number, because it can be changed into a prime (20530247) 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, 31759 + ... + 32398.

Almost surely, 2^20530240 is an apocalyptic number.

20530240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20530240 is an abundant number, since it is smaller than the sum of its proper divisors (28358156).

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

20530240 is an equidigital number, since it uses as much as digits as its factorization.

20530240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64174 (or 64164 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 16.

The square root of 20530240 is about 4531.0307878009. The cubic root of 20530240 is about 273.8196906310.

Adding to 20530240 its reverse (4203502), we get a palindrome (24733742).

The spelling of 20530240 in words is "twenty million, five hundred thirty thousand, two hundred forty".