20845639089 has 126 divisors (see below), whose sum is σ = 35705824518. Its totient is φ = 12154665600.

The previous prime is 20845639057. The next prime is 20845639091. The reversal of 20845639089 is 98093654802.

20845639089 is a `hidden beast` number, since 20 + 8 + 456 + 3 + 90 + 89 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 4912888464 + 15932750625 = 70092^2 + 126225^2 .

It is not a de Polignac number, because 20845639089 - 2⁵ = 20845639057 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20845639019) by changing a digit.

It is a polite number, since it can be written in 125 ways as a sum of consecutive naturals, for example, 74183629 + ... + 74183909.

Almost surely, 2^20845639089 is an apocalyptic number.

20845639089 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

20845639089 is a deficient number, since it is larger than the sum of its proper divisors (14860185429).

20845639089 is an equidigital number, since it uses as much as digits as its factorization.

20845639089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 379 (or 324 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 54.

The spelling of 20845639089 in words is "twenty billion, eight hundred forty-five million, six hundred thirty-nine thousand, eighty-nine".