21284829 has 16 divisors (see below), whose sum is σ = 31968000. Its totient is φ = 13994208.

The previous prime is 21284801. The next prime is 21284839. The reversal of 21284829 is 92848212.

It is not a de Polignac number, because 21284829 - 2⁵ = 21284797 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21284793 and 21284802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21284839) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3429 + ... + 7370.

It is an arithmetic number, because the mean of its divisors is an integer number (1998000).

Almost surely, 2^21284829 is an apocalyptic number.

It is an amenable number.

21284829 is a deficient number, since it is larger than the sum of its proper divisors (10683171).

21284829 is a wasteful number, since it uses less digits than its factorization.

21284829 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10881 (or 10875 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 21284829 is about 4613.5484174332. The cubic root of 21284829 is about 277.1341563221.

The spelling of 21284829 in words is "twenty-one million, two hundred eighty-four thousand, eight hundred twenty-nine".