21208298 has 4 divisors (see below), whose sum is σ = 31812450. Its totient is φ = 10604148.

The previous prime is 21208259. The next prime is 21208349. The reversal of 21208298 is 89280212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 17833729 + 3374569 = 4223^2 + 1837^2 .

It is an unprimeable number.

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, 5302073 + ... + 5302076.

Almost surely, 2^21208298 is an apocalyptic number.

21208298 is a deficient number, since it is larger than the sum of its proper divisors (10604152).

21208298 is a wasteful number, since it uses less digits than its factorization.

21208298 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10604151.

The product of its (nonzero) digits is 4608, while the sum is 32.

The square root of 21208298 is about 4605.2467903469. The cubic root of 21208298 is about 276.8016060834.

The spelling of 21208298 in words is "twenty-one million, two hundred eight thousand, two hundred ninety-eight".