21212210003 has 4 divisors (see below), whose sum is σ = 22459987080. Its totient is φ = 19964432928.

The previous prime is 21212209951. The next prime is 21212210059. The reversal of 21212210003 is 30001221212.

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 21212210003 - 2²⁰ = 21211161427 is a prime.

It is a super-2 number, since 2×21212210003² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21212210003.

It is not an unprimeable number, because it can be changed into a prime (21212213003) 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, 623888513 + ... + 623888546.

It is an arithmetic number, because the mean of its divisors is an integer number (5614996770).

Almost surely, 2^21212210003 is an apocalyptic number.

21212210003 is a deficient number, since it is larger than the sum of its proper divisors (1247777077).

21212210003 is a wasteful number, since it uses less digits than its factorization.

21212210003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1247777076.

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21212210003 its reverse (30001221212), we get a palindrome (51213431215).

The spelling of 21212210003 in words is "twenty-one billion, two hundred twelve million, two hundred ten thousand, three".