21670338 has 16 divisors (see below), whose sum is σ = 43407936. Its totient is φ = 7212240.

The previous prime is 21670331. The next prime is 21670339. The reversal of 21670338 is 83307612.

It is not an unprimeable number, because it can be changed into a prime (21670331) 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 7 ways as a sum of consecutive naturals, for example, 2028 + ... + 6888.

It is an arithmetic number, because the mean of its divisors is an integer number (2712996).

Almost surely, 2^21670338 is an apocalyptic number.

21670338 is an abundant number, since it is smaller than the sum of its proper divisors (21737598).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21670338 is a wasteful number, since it uses less digits than its factorization.

21670338 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5609.

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 21670338 is about 4655.1410290130. The cubic root of 21670338 is about 278.7972988437.

The spelling of 21670338 in words is "twenty-one million, six hundred seventy thousand, three hundred thirty-eight".