20744280 has 96 divisors (see below), whose sum is σ = 69778800. Its totient is φ = 5338368.

The previous prime is 20744279. The next prime is 20744287. The reversal of 20744280 is 8244702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20744287) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9447 + ... + 11433.

Almost surely, 2^20744280 is an apocalyptic number.

20744280 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 20744280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34889400).

20744280 is an abundant number, since it is smaller than the sum of its proper divisors (49034520).

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

20744280 is a wasteful number, since it uses less digits than its factorization.

20744280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2033 (or 2026 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 27.

The square root of 20744280 is about 4554.5888947302. The cubic root of 20744280 is about 274.7679806072.

Adding to 20744280 its reverse (8244702), we get a palindrome (28988982).

The spelling of 20744280 in words is "twenty million, seven hundred forty-four thousand, two hundred eighty".