20730828 has 12 divisors (see below), whose sum is σ = 48371960. Its totient is φ = 6910272.

The previous prime is 20730823. The next prime is 20730839. The reversal of 20730828 is 82803702.

It is a tau number, because it is divible by the number of its divisors (12).

It is a junction number, because it is equal to n+sod(n) for n = 20730795 and 20730804.

It is not an unprimeable number, because it can be changed into a prime (20730823) 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, 863773 + ... + 863796.

Almost surely, 2^20730828 is an apocalyptic number.

It is an amenable number.

20730828 is an abundant number, since it is smaller than the sum of its proper divisors (27641132).

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

20730828 is a wasteful number, since it uses less digits than its factorization.

20730828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1727576 (or 1727574 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 20730828 is about 4553.1119028638. Note that the first 3 decimals coincide. The cubic root of 20730828 is about 274.7085750247.

The spelling of 20730828 in words is "twenty million, seven hundred thirty thousand, eight hundred twenty-eight".