21047168 has 16 divisors (see below), whose sum is σ = 41930160. Its totient is φ = 10523520.

The previous prime is 21047153. The next prime is 21047183. The reversal of 21047168 is 86174012.

It is an interprime number because it is at equal distance from previous prime (21047153) and next prime (21047183).

It is a tau number, because it is divible by the number of its divisors (16).

It is a self number, because there is not a number n which added to its sum of digits gives 21047168.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82088 + ... + 82343.

It is an arithmetic number, because the mean of its divisors is an integer number (2620635).

Almost surely, 2^21047168 is an apocalyptic number.

It is an amenable number.

21047168 is a deficient number, since it is larger than the sum of its proper divisors (20882992).

21047168 is an equidigital number, since it uses as much as digits as its factorization.

21047168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164445 (or 164433 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 21047168 is about 4587.7192590654. The cubic root of 21047168 is about 276.0988233947.

The spelling of 21047168 in words is "twenty-one million, forty-seven thousand, one hundred sixty-eight".