21286735838 has 8 divisors (see below), whose sum is σ = 32960107200. Its totient is φ = 10300033440.

The previous prime is 21286735837. The next prime is 21286735853. The reversal of 21286735838 is 83853768212.

It is a happy number.

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 21286735838.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21286735837) 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, 171667163 + ... + 171667286.

It is an arithmetic number, because the mean of its divisors is an integer number (4120013400).

Almost surely, 2^21286735838 is an apocalyptic number.

21286735838 is a deficient number, since it is larger than the sum of its proper divisors (11673371362).

21286735838 is a wasteful number, since it uses less digits than its factorization.

21286735838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343334482.

The product of its digits is 3870720, while the sum is 53.

The spelling of 21286735838 in words is "twenty-one billion, two hundred eighty-six million, seven hundred thirty-five thousand, eight hundred thirty-eight".