21838706018 has 8 divisors (see below), whose sum is σ = 32759085612. Its totient is φ = 10919010816.

The previous prime is 21838705979. The next prime is 21838706023. The reversal of 21838706018 is 81060783812.

It can be written as a sum of positive squares in 2 ways, for example, as 19919652769 + 1919053249 = 141137^2 + 43807^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21838706018.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82055 + ... + 224522.

Almost surely, 2^21838706018 is an apocalyptic number.

21838706018 is a deficient number, since it is larger than the sum of its proper divisors (10920379594).

21838706018 is a wasteful number, since it uses less digits than its factorization.

21838706018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342196.

The product of its (nonzero) digits is 129024, while the sum is 44.

The spelling of 21838706018 in words is "twenty-one billion, eight hundred thirty-eight million, seven hundred six thousand, eighteen".