20389608081 has 6 divisors (see below), whose sum is σ = 29451656130. Its totient is φ = 13593072048.

The previous prime is 20389608061. The next prime is 20389608133. The reversal of 20389608081 is 18080698302.

20389608081 is a `hidden beast` number, since 2 + 0 + 38 + 9 + 608 + 0 + 8 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 18121467456 + 2268140625 = 134616^2 + 47625^2 .

It is not a de Polignac number, because 20389608081 - 2⁹ = 20389607569 is a prime.

It is a super-2 number, since 2×20389608081² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20389608061) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1132755996 + ... + 1132756013.

It is an arithmetic number, because the mean of its divisors is an integer number (4908609355).

Almost surely, 2^20389608081 is an apocalyptic number.

It is an amenable number.

20389608081 is a deficient number, since it is larger than the sum of its proper divisors (9062048049).

20389608081 is a wasteful number, since it uses less digits than its factorization.

20389608081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2265512015 (or 2265512012 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The spelling of 20389608081 in words is "twenty billion, three hundred eighty-nine million, six hundred eight thousand, eighty-one".