21074717 has 4 divisors (see below), whose sum is σ = 21371616. Its totient is φ = 20777820.

The previous prime is 21074689. The next prime is 21074737. The reversal of 21074717 is 71747012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21074717 - 2²⁰ = 20026141 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21074717.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21074737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 148343 + ... + 148484.

It is an arithmetic number, because the mean of its divisors is an integer number (5342904).

Almost surely, 2^21074717 is an apocalyptic number.

It is an amenable number.

21074717 is a deficient number, since it is larger than the sum of its proper divisors (296899).

21074717 is an equidigital number, since it uses as much as digits as its factorization.

21074717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296898.

The product of its (nonzero) digits is 2744, while the sum is 29.

The square root of 21074717 is about 4590.7207495120. The cubic root of 21074717 is about 276.2192343726.

The spelling of 21074717 in words is "twenty-one million, seventy-four thousand, seven hundred seventeen".