21111021202 has 4 divisors (see below), whose sum is σ = 31666531806. Its totient is φ = 10555510600.

The previous prime is 21111021181. The next prime is 21111021203. The reversal of 21111021202 is 20212011112.

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., 14411762401 + 6699258801 = 120049^2 + 81849^2 .

It is not an unprimeable number, because it can be changed into a prime (21111021203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5277755299 + ... + 5277755302.

Almost surely, 2^21111021202 is an apocalyptic number.

21111021202 is a deficient number, since it is larger than the sum of its proper divisors (10555510604).

21111021202 is a wasteful number, since it uses less digits than its factorization.

21111021202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10555510603.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21111021202 its reverse (20212011112), we get a palindrome (41323032314).

The spelling of 21111021202 in words is "twenty-one billion, one hundred eleven million, twenty-one thousand, two hundred two".