21327198591 has 8 divisors (see below), whose sum is σ = 28702024704. Its totient is φ = 14085252440.

The previous prime is 21327198583. The next prime is 21327198631. The reversal of 21327198591 is 19589172312.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21327198591 - 2³ = 21327198583 is a prime.

It is a super-3 number, since 3×21327198591³ (a number of 32 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21327198591.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21327198521) 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 7 ways as a sum of consecutive naturals, for example, 33219615 + ... + 33220256.

It is an arithmetic number, because the mean of its divisors is an integer number (3587753088).

Almost surely, 2^21327198591 is an apocalyptic number.

21327198591 is a deficient number, since it is larger than the sum of its proper divisors (7374826113).

21327198591 is a wasteful number, since it uses less digits than its factorization.

21327198591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66439981.

The product of its digits is 272160, while the sum is 48.

The spelling of 21327198591 in words is "twenty-one billion, three hundred twenty-seven million, one hundred ninety-eight thousand, five hundred ninety-one".