20242240 has 84 divisors (see below), whose sum is σ = 51887628. Its totient is φ = 7495680.

The previous prime is 20242213. The next prime is 20242247. The reversal of 20242240 is 4224202.

It can be written as a sum of positive squares in 6 ways, for example, as 5125696 + 15116544 = 2264^2 + 3888^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20242247) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 331810 + ... + 331870.

Almost surely, 2^20242240 is an apocalyptic number.

20242240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20242240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25943814).

20242240 is an abundant number, since it is smaller than the sum of its proper divisors (31645388).

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

20242240 is an equidigital number, since it uses as much as digits as its factorization.

20242240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156 (or 85 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 16.

The square root of 20242240 is about 4499.1376951589. The cubic root of 20242240 is about 272.5332675486.

Adding to 20242240 its reverse (4224202), we get a palindrome (24466442).

The spelling of 20242240 in words is "twenty million, two hundred forty-two thousand, two hundred forty".