20387256089 has 2 divisors, whose sum is σ = 20387256090. Its totient is φ = 20387256088.

The previous prime is 20387256047. The next prime is 20387256167. The reversal of 20387256089 is 98065278302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10507890064 + 9879366025 = 102508^2 + 99395^2 .

It is a cyclic number.

It is not a de Polignac number, because 20387256089 - 2¹⁶ = 20387190553 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20387216089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10193628044 + 10193628045.

It is an arithmetic number, because the mean of its divisors is an integer number (10193628045).

Almost surely, 2^20387256089 is an apocalyptic number.

It is an amenable number.

20387256089 is a deficient number, since it is larger than the sum of its proper divisors (1).

20387256089 is an equidigital number, since it uses as much as digits as its factorization.

20387256089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1451520, while the sum is 50.

The spelling of 20387256089 in words is "twenty billion, three hundred eighty-seven million, two hundred fifty-six thousand, eighty-nine".