21202 has 4 divisors (see below), whose sum is σ = 31806.
Its totient is φ = 10600.
The previous prime is 21193. The next prime is 21211. The reversal of 21202 is 20212.
Adding to 21202 its reverse (20212), we get a palindrome (41414).
Subtracting from 21202 its reverse (20212), we obtain a triangular number (990 = T44).
It is a happy number.
It is a semiprime because it is the product of two primes.
It is an interprime number because it is at equal distance from previous prime (21193) and next prime (21211).
It can be written as a sum of positive squares in only one way, i.e., 14641 + 6561 = 121^2 + 81^2
It is an unprimeable number.
It is a pernicious number, because its binary representation contains a prime number (7) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5299 + ... + 5302.
221202 is an apocalyptic number.
21202 is a deficient number, since it is larger than the sum of its proper divisors (10604).
21202 is a wasteful number, since it uses less digits than its factorization.
21202 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 10603.
The product of its (nonzero) digits is 8, while the sum is 7.
The square root of 21202 is about 145.6090656518.
The cubic root of 21202 is about 27.6774203773.
The spelling of 21202 in words is "twenty-one thousand, two hundred two", and thus it is an iban number.