21202023211 has 4 divisors (see below), whose sum is σ = 21549597424. Its totient is φ = 20854449000.

The previous prime is 21202023179. The next prime is 21202023233. The reversal of 21202023211 is 11232020212.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21202023211 - 2⁵ = 21202023179 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21202023251) 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, 173787015 + ... + 173787136.

It is an arithmetic number, because the mean of its divisors is an integer number (5387399356).

Almost surely, 2^21202023211 is an apocalyptic number.

21202023211 is a deficient number, since it is larger than the sum of its proper divisors (347574213).

21202023211 is an equidigital number, since it uses as much as digits as its factorization.

21202023211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 347574212.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21202023211 its reverse (11232020212), we get a palindrome (32434043423).

The spelling of 21202023211 in words is "twenty-one billion, two hundred two million, twenty-three thousand, two hundred eleven".