21579127 has 2 divisors, whose sum is σ = 21579128. Its totient is φ = 21579126.

The previous prime is 21579113. The next prime is 21579143. The reversal of 21579127 is 72197512.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21579127 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21579092 and 21579101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21579167) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10789563 + 10789564.

It is an arithmetic number, because the mean of its divisors is an integer number (10789564).

Almost surely, 2^21579127 is an apocalyptic number.

21579127 is a deficient number, since it is larger than the sum of its proper divisors (1).

21579127 is an equidigital number, since it uses as much as digits as its factorization.

21579127 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8820, while the sum is 34.

The square root of 21579127 is about 4645.3338954267. Note that the first 3 decimals coincide. The cubic root of 21579127 is about 278.4055938055.

The spelling of 21579127 in words is "twenty-one million, five hundred seventy-nine thousand, one hundred twenty-seven".