21202102011 has 4 divisors (see below), whose sum is σ = 28269469352. Its totient is φ = 14134734672.

The previous prime is 21202102003. The next prime is 21202102021. The reversal of 21202102011 is 11020120212.

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

It is not a de Polignac number, because 21202102011 - 2³ = 21202102003 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21202102001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3533683666 + ... + 3533683671.

It is an arithmetic number, because the mean of its divisors is an integer number (7067367338).

Almost surely, 2^21202102011 is an apocalyptic number.

21202102011 is a deficient number, since it is larger than the sum of its proper divisors (7067367341).

21202102011 is an equidigital number, since it uses as much as digits as its factorization.

21202102011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7067367340.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21202102011 its reverse (11020120212), we get a palindrome (32222222223).

The spelling of 21202102011 in words is "twenty-one billion, two hundred two million, one hundred two thousand, eleven".