20988081387 has 48 divisors (see below), whose sum is σ = 37944641280. Its totient is φ = 10882973376.

The previous prime is 20988081353. The next prime is 20988081403. The reversal of 20988081387 is 78318088902.

20988081387 is a `hidden beast` number, since 20 + 98 + 80 + 81 + 387 = 666.

It is not a de Polignac number, because 20988081387 - 2²³ = 20979692779 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20988081887) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 168853 + ... + 265494.

It is an arithmetic number, because the mean of its divisors is an integer number (790513360).

Almost surely, 2^20988081387 is an apocalyptic number.

20988081387 is a deficient number, since it is larger than the sum of its proper divisors (16956559893).

20988081387 is a wasteful number, since it uses less digits than its factorization.

20988081387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 434432 (or 434429 counting only the distinct ones).

The product of its (nonzero) digits is 1548288, while the sum is 54.

The spelling of 20988081387 in words is "twenty billion, nine hundred eighty-eight million, eighty-one thousand, three hundred eighty-seven".