21121211003 has 4 divisors (see below), whose sum is σ = 21326271408. Its totient is φ = 20916150600.

The previous prime is 21121210987. The next prime is 21121211011. The reversal of 21121211003 is 30011212112.

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 21121211003 - 2⁴ = 21121210987 is a prime.

It is a super-2 number, since 2×21121211003² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21121211303) 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, 102530048 + ... + 102530253.

It is an arithmetic number, because the mean of its divisors is an integer number (5331567852).

Almost surely, 2^21121211003 is an apocalyptic number.

21121211003 is a deficient number, since it is larger than the sum of its proper divisors (205060405).

21121211003 is a wasteful number, since it uses less digits than its factorization.

21121211003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205060404.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 21121211003 its reverse (30011212112), we get a palindrome (51132423115).

The spelling of 21121211003 in words is "twenty-one billion, one hundred twenty-one million, two hundred eleven thousand, three".