21838206 has 16 divisors (see below), whose sum is σ = 47036304. Its totient is φ = 6719424.

The previous prime is 21838171. The next prime is 21838231. The reversal of 21838206 is 60283812.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 139911 + ... + 140066.

It is an arithmetic number, because the mean of its divisors is an integer number (2939769).

Almost surely, 2^21838206 is an apocalyptic number.

21838206 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21838206 is an abundant number, since it is smaller than the sum of its proper divisors (25198098).

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

21838206 is a wasteful number, since it uses less digits than its factorization.

21838206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 279995.

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 21838206 is about 4673.1366339965. The cubic root of 21838206 is about 279.5153435573.

The spelling of 21838206 in words is "twenty-one million, eight hundred thirty-eight thousand, two hundred six".