21895339087439 has 4 divisors (see below), whose sum is σ = 21895351945656. Its totient is φ = 21895326229224.

The previous prime is 21895339087417. The next prime is 21895339087469. The reversal of 21895339087439 is 93478093359812.

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

It is a cyclic number.

It is not a de Polignac number, because 21895339087439 - 2⁴⁴ = 4303153043023 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 (21895339087469) 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, 3398744 + ... + 7439229.

It is an arithmetic number, because the mean of its divisors is an integer number (5473837986414).

Almost surely, 2^{21895339087439} is an apocalyptic number.

21895339087439 is a deficient number, since it is larger than the sum of its proper divisors (12858217).

21895339087439 is a wasteful number, since it uses less digits than its factorization.

21895339087439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12858216.

The product of its (nonzero) digits is 352719360, while the sum is 71.

The spelling of 21895339087439 in words is "twenty-one trillion, eight hundred ninety-five billion, three hundred thirty-nine million, eighty-seven thousand, four hundred thirty-nine".