20240720 has 30 divisors (see below), whose sum is σ = 47153418. Its totient is φ = 8080192.

The previous prime is 20240683. The next prime is 20240723. The reversal of 20240720 is 2704202.

It can be written as a sum of positive squares in only one way, i.e., 16192576 + 4048144 = 4024^2 + 2012^2 .

It is a super-2 number, since 2×20240720² = 819373492236800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20240723) 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 5 ways as a sum of consecutive naturals, for example, 39989 + ... + 40491.

Almost surely, 2^20240720 is an apocalyptic number.

20240720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20240720 is an abundant number, since it is smaller than the sum of its proper divisors (26912698).

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

20240720 is an frugal number, since it uses more digits than its factorization.

20240720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1019 (or 510 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 17.

The square root of 20240720 is about 4498.9687707296. The cubic root of 20240720 is about 272.5264458244.

Subtracting from 20240720 its sum of digits (17), we obtain a triangular number (20240703 = T₆₃₆₂).

Adding to 20240720 its reverse (2704202), we get a palindrome (22944922).

The spelling of 20240720 in words is "twenty million, two hundred forty thousand, seven hundred twenty".