20828456109 has 12 divisors (see below), whose sum is σ = 30090045856. Its totient is φ = 13883561352.

The previous prime is 20828456101. The next prime is 20828456137. The reversal of 20828456109 is 90165482802.

20828456109 is a `hidden beast` number, since 2 + 0 + 8 + 2 + 84 + 561 + 0 + 9 = 666.

It is not a de Polignac number, because 20828456109 - 2³ = 20828456101 is a prime.

It is a super-3 number, since 3×20828456109³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20828456101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 108187 + ... + 231000.

Almost surely, 2^20828456109 is an apocalyptic number.

It is an amenable number.

20828456109 is a deficient number, since it is larger than the sum of its proper divisors (9261589747).

20828456109 is a wasteful number, since it uses less digits than its factorization.

20828456109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346016 (or 346013 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The spelling of 20828456109 in words is "twenty billion, eight hundred twenty-eight million, four hundred fifty-six thousand, one hundred nine".