21021211201 has 4 divisors (see below), whose sum is σ = 21022388992. Its totient is φ = 21020033412.

The previous prime is 21021211193. The next prime is 21021211213. The reversal of 21021211201 is 10211212012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21021211201 - 2³ = 21021211193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21021211801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 561705 + ... + 597958.

It is an arithmetic number, because the mean of its divisors is an integer number (5255597248).

Almost surely, 2^21021211201 is an apocalyptic number.

It is an amenable number.

21021211201 is a deficient number, since it is larger than the sum of its proper divisors (1177791).

21021211201 is a wasteful number, since it uses less digits than its factorization.

21021211201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1177790.

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

Adding to 21021211201 its reverse (10211212012), we get a palindrome (31232423213).

The spelling of 21021211201 in words is "twenty-one billion, twenty-one million, two hundred eleven thousand, two hundred one".