21381202 has 16 divisors (see below), whose sum is σ = 32563800. Its totient is φ = 10528128.

The previous prime is 21381181. The next prime is 21381203. The reversal of 21381202 is 20218312.

It can be written as a sum of positive squares in 4 ways, for example, as 16232841 + 5148361 = 4029^2 + 2269^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21381202.

It is not an unprimeable number, because it can be changed into a prime (21381203) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46558 + ... + 47014.

Almost surely, 2^21381202 is an apocalyptic number.

21381202 is a deficient number, since it is larger than the sum of its proper divisors (11182598).

21381202 is a wasteful number, since it uses less digits than its factorization.

21381202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 765.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 21381202 is about 4623.9811850828. The cubic root of 21381202 is about 277.5517940279.

Adding to 21381202 its reverse (20218312), we get a palindrome (41599514).

The spelling of 21381202 in words is "twenty-one million, three hundred eighty-one thousand, two hundred two".