21416775 has 12 divisors (see below), whose sum is σ = 35409192. Its totient is φ = 11422240.

The previous prime is 21416737. The next prime is 21416779. The reversal of 21416775 is 57761412.

It is not a de Polignac number, because 21416775 - 2¹² = 21412679 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21416779) 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 in 11 ways as a sum of consecutive naturals, for example, 142704 + ... + 142853.

It is an arithmetic number, because the mean of its divisors is an integer number (2950766).

Almost surely, 2^21416775 is an apocalyptic number.

21416775 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21416775 is a deficient number, since it is larger than the sum of its proper divisors (13992417).

21416775 is a wasteful number, since it uses less digits than its factorization.

21416775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285570 (or 285565 counting only the distinct ones).

The product of its digits is 11760, while the sum is 33.

The square root of 21416775 is about 4627.8261635459. The cubic root of 21416775 is about 277.7056344500.

The spelling of 21416775 in words is "twenty-one million, four hundred sixteen thousand, seven hundred seventy-five".