21211211111203 has 4 divisors (see below), whose sum is σ = 22458929411880. Its totient is φ = 19963492810528.

The previous prime is 21211211111197. The next prime is 21211211111231. The reversal of 21211211111203 is 30211111211212.

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 21211211111203 - 2⁴¹ = 19012187855651 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21211211111303) 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, 623859150313 + ... + 623859150346.

It is an arithmetic number, because the mean of its divisors is an integer number (5614732352970).

Almost surely, 2^{21211211111203} is an apocalyptic number.

21211211111203 is a deficient number, since it is larger than the sum of its proper divisors (1247718300677).

21211211111203 is a wasteful number, since it uses less digits than its factorization.

21211211111203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1247718300676.

The product of its (nonzero) digits is 48, while the sum is 19.

Adding to 21211211111203 its reverse (30211111211212), we get a palindrome (51422322322415).

The spelling of 21211211111203 in words is "twenty-one trillion, two hundred eleven billion, two hundred eleven million, one hundred eleven thousand, two hundred three".