21959338591 has 8 divisors (see below), whose sum is σ = 22833166464. Its totient is φ = 21095852160.

The previous prime is 21959338553. The next prime is 21959338603. The reversal of 21959338591 is 19583395912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21959338591 - 2¹³ = 21959330399 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 (21959338091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2581030 + ... + 2589523.

It is an arithmetic number, because the mean of its divisors is an integer number (2854145808).

Almost surely, 2^21959338591 is an apocalyptic number.

21959338591 is a deficient number, since it is larger than the sum of its proper divisors (873827873).

21959338591 is a wasteful number, since it uses less digits than its factorization.

21959338591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5170721.

The product of its digits is 2624400, while the sum is 55.

The spelling of 21959338591 in words is "twenty-one billion, nine hundred fifty-nine million, three hundred thirty-eight thousand, five hundred ninety-one".