20898188135999 has 4 divisors (see below), whose sum is σ = 20900197780800. Its totient is φ = 20896178491200.

The previous prime is 20898188135933. The next prime is 20898188136031. The reversal of 20898188135999 is 99953188189802.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20898188135999 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20898188135899) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1004806802 + ... + 1004827599.

It is an arithmetic number, because the mean of its divisors is an integer number (5225049445200).

Almost surely, 2^{20898188135999} is an apocalyptic number.

20898188135999 is a deficient number, since it is larger than the sum of its proper divisors (2009644801).

20898188135999 is a wasteful number, since it uses less digits than its factorization.

20898188135999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2009644800.

The product of its (nonzero) digits is 806215680, while the sum is 80.

The spelling of 20898188135999 in words is "twenty trillion, eight hundred ninety-eight billion, one hundred eighty-eight million, one hundred thirty-five thousand, nine hundred ninety-nine".