21616127 has 4 divisors (see below), whose sum is σ = 23278920. Its totient is φ = 19953336.

The previous prime is 21616123. The next prime is 21616139. The reversal of 21616127 is 72161612.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21616127 - 2² = 21616123 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21616096 and 21616105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21616123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 831377 + ... + 831402.

It is an arithmetic number, because the mean of its divisors is an integer number (5819730).

Almost surely, 2^21616127 is an apocalyptic number.

21616127 is a deficient number, since it is larger than the sum of its proper divisors (1662793).

21616127 is a wasteful number, since it uses less digits than its factorization.

21616127 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1662792.

The product of its digits is 1008, while the sum is 26.

The square root of 21616127 is about 4649.3146806814. The cubic root of 21616127 is about 278.5646228700.

Adding to 21616127 its reverse (72161612), we get a palindrome (93777739).

The spelling of 21616127 in words is "twenty-one million, six hundred sixteen thousand, one hundred twenty-seven".