21447004 has 6 divisors (see below), whose sum is σ = 37532264. Its totient is φ = 10723500.

The previous prime is 21446989. The next prime is 21447007. The reversal of 21447004 is 40074412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21447007) 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 as a sum of consecutive naturals, namely, 2680872 + ... + 2680879.

Almost surely, 2^21447004 is an apocalyptic number.

It is an amenable number.

21447004 is a deficient number, since it is larger than the sum of its proper divisors (16085260).

21447004 is a wasteful number, since it uses less digits than its factorization.

21447004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5361755 (or 5361753 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 22.

The square root of 21447004 is about 4631.0910161645. The cubic root of 21447004 is about 277.8362301643.

The spelling of 21447004 in words is "twenty-one million, four hundred forty-seven thousand, four".