21047673 has 4 divisors (see below), whose sum is σ = 28063568. Its totient is φ = 14031780.

The previous prime is 21047671. The next prime is 21047713. The reversal of 21047673 is 37674012.

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 not a de Polignac number, because 21047673 - 2¹ = 21047671 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 21047673.

It is not an unprimeable number, because it can be changed into a prime (21047671) 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, 3507943 + ... + 3507948.

It is an arithmetic number, because the mean of its divisors is an integer number (7015892).

Almost surely, 2^21047673 is an apocalyptic number.

It is an amenable number.

21047673 is a deficient number, since it is larger than the sum of its proper divisors (7015895).

21047673 is an equidigital number, since it uses as much as digits as its factorization.

21047673 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7015894.

The product of its (nonzero) digits is 7056, while the sum is 30.

The square root of 21047673 is about 4587.7742969767. The cubic root of 21047673 is about 276.1010315902.

The spelling of 21047673 in words is "twenty-one million, forty-seven thousand, six hundred seventy-three".