21791911339351 has 4 divisors (see below), whose sum is σ = 21791932953952. Its totient is φ = 21791889724752.

The previous prime is 21791911339213. The next prime is 21791911339423. The reversal of 21791911339351 is 15393311919712.

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 21791911339351 - 2⁹ = 21791911338839 is a prime.

It is a super-2 number, since 2×21791911339351² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21791911339292 and 21791911339301.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21791911334351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9216990 + ... + 11337403.

It is an arithmetic number, because the mean of its divisors is an integer number (5447983238488).

Almost surely, 2^{21791911339351} is an apocalyptic number.

21791911339351 is a deficient number, since it is larger than the sum of its proper divisors (21614601).

21791911339351 is a wasteful number, since it uses less digits than its factorization.

21791911339351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21614600.

The product of its digits is 1377810, while the sum is 55.

The spelling of 21791911339351 in words is "twenty-one trillion, seven hundred ninety-one billion, nine hundred eleven million, three hundred thirty-nine thousand, three hundred fifty-one".