20672320 has 28 divisors (see below), whose sum is σ = 49226724. Its totient is φ = 8268800.

The previous prime is 20672299. The next prime is 20672321. The reversal of 20672320 is 2327602.

It can be written as a sum of positive squares in 2 ways, for example, as 13660416 + 7011904 = 3696^2 + 2648^2 .

It is a super-3 number, since 3×20672320³ (a number of 23 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20672291 and 20672300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20672321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31981 + ... + 32620.

Almost surely, 2^20672320 is an apocalyptic number.

20672320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20672320 is an abundant number, since it is smaller than the sum of its proper divisors (28554404).

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

20672320 is an equidigital number, since it uses as much as digits as its factorization.

20672320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64618 (or 64608 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 22.

The square root of 20672320 is about 4546.6823069135. The cubic root of 20672320 is about 274.4498975692.

Adding to 20672320 its reverse (2327602), we get a palindrome (22999922).

The spelling of 20672320 in words is "twenty million, six hundred seventy-two thousand, three hundred twenty".