21942208 has 14 divisors (see below), whose sum is σ = 43541696. Its totient is φ = 10971072.

The previous prime is 21942199. The next prime is 21942209. The reversal of 21942208 is 80224912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21942209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171360 + ... + 171487.

Almost surely, 2^21942208 is an apocalyptic number.

It is an amenable number.

21942208 is a deficient number, since it is larger than the sum of its proper divisors (21599488).

21942208 is an equidigital number, since it uses as much as digits as its factorization.

21942208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342859 (or 342849 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 21942208 is about 4684.2510607353. The cubic root of 21942208 is about 279.9583611551.

The spelling of 21942208 in words is "twenty-one million, nine hundred forty-two thousand, two hundred eight".