21191327 has 8 divisors (see below), whose sum is σ = 22358400. Its totient is φ = 20029464.

The previous prime is 21191309. The next prime is 21191329. The reversal of 21191327 is 72319112.

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 21191327 - 2⁶ = 21191263 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21191296 and 21191305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21191329) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9374 + ... + 11412.

It is an arithmetic number, because the mean of its divisors is an integer number (2794800).

Almost surely, 2^21191327 is an apocalyptic number.

21191327 is a deficient number, since it is larger than the sum of its proper divisors (1167073).

21191327 is a wasteful number, since it uses less digits than its factorization.

21191327 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2605.

The product of its digits is 756, while the sum is 26.

The square root of 21191327 is about 4603.4038493271. The cubic root of 21191327 is about 276.7277536440.

The spelling of 21191327 in words is "twenty-one million, one hundred ninety-one thousand, three hundred twenty-seven".