21643919634359 has 12 divisors (see below), whose sum is σ = 23790573845640. Its totient is φ = 19676166694800.

The previous prime is 21643919634341. The next prime is 21643919634409. The reversal of 21643919634359 is 95343691934612.

It is a de Polignac number, because none of the positive numbers 2^k-21643919634359 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21643919634295 and 21643919634304.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21643919634959) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22684589 + ... + 23619449.

It is an arithmetic number, because the mean of its divisors is an integer number (1982547820470).

Almost surely, 2^{21643919634359} is an apocalyptic number.

21643919634359 is a deficient number, since it is larger than the sum of its proper divisors (2146654211281).

21643919634359 is a wasteful number, since it uses less digits than its factorization.

21643919634359 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1126222 (or 1126211 counting only the distinct ones).

The product of its digits is 113374080, while the sum is 65.

The spelling of 21643919634359 in words is "twenty-one trillion, six hundred forty-three billion, nine hundred nineteen million, six hundred thirty-four thousand, three hundred fifty-nine".