21394683238 has 4 divisors (see below), whose sum is σ = 32092024860. Its totient is φ = 10697341618.

The previous prime is 21394683223. The next prime is 21394683301. The reversal of 21394683238 is 83238649312.

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

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 21394683191 and 21394683200.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5348670808 + ... + 5348670811.

It is an arithmetic number, because the mean of its divisors is an integer number (8023006215).

Almost surely, 2^21394683238 is an apocalyptic number.

21394683238 is a deficient number, since it is larger than the sum of its proper divisors (10697341622).

21394683238 is a wasteful number, since it uses less digits than its factorization.

21394683238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10697341621.

The product of its digits is 1492992, while the sum is 49.

The spelling of 21394683238 in words is "twenty-one billion, three hundred ninety-four million, six hundred eighty-three thousand, two hundred thirty-eight".