21838706017 has 4 divisors (see below), whose sum is σ = 21844890900. Its totient is φ = 21832521136.

The previous prime is 21838705979. The next prime is 21838706023. The reversal of 21838706017 is 71060783812.

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

It can be written as a sum of positive squares in 2 ways, for example, as 20184169041 + 1654536976 = 142071^2 + 40676^2 .

It is a cyclic number.

It is not a de Polignac number, because 21838706017 - 2²³ = 21830317409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21838703017) 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, 3087142 + ... + 3094207.

It is an arithmetic number, because the mean of its divisors is an integer number (5461222725).

Almost surely, 2^21838706017 is an apocalyptic number.

It is an amenable number.

21838706017 is a deficient number, since it is larger than the sum of its proper divisors (6184883).

21838706017 is an equidigital number, since it uses as much as digits as its factorization.

21838706017 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6184882.

The product of its (nonzero) digits is 112896, while the sum is 43.

The spelling of 21838706017 in words is "twenty-one billion, eight hundred thirty-eight million, seven hundred six thousand, seventeen".