21213202 has 4 divisors (see below), whose sum is σ = 31819806. Its totient is φ = 10606600.

The previous prime is 21213193. The next prime is 21213251. The reversal of 21213202 is 20231212.

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., 13039321 + 8173881 = 3611^2 + 2859^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5303299 + ... + 5303302.

Almost surely, 2^21213202 is an apocalyptic number.

21213202 is a deficient number, since it is larger than the sum of its proper divisors (10606604).

21213202 is a wasteful number, since it uses less digits than its factorization.

21213202 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10606603.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 21213202 is about 4605.7791957496. The cubic root of 21213202 is about 276.8229394072.

Adding to 21213202 its reverse (20231212), we get a palindrome (41444414).

The spelling of 21213202 in words is "twenty-one million, two hundred thirteen thousand, two hundred two".