21003213111 has 16 divisors (see below), whose sum is σ = 29481830400. Its totient is φ = 13263550848.

The previous prime is 21003213097. The next prime is 21003213221. The reversal of 21003213111 is 11131230012.

It is a happy number.

It is not a de Polignac number, because 21003213111 - 2⁶ = 21003213047 is a prime.

It is a super-2 number, since 2×21003213111² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21003213311) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 584415 + ... + 619311.

It is an arithmetic number, because the mean of its divisors is an integer number (1842614400).

Almost surely, 2^21003213111 is an apocalyptic number.

21003213111 is a deficient number, since it is larger than the sum of its proper divisors (8478617289).

21003213111 is a wasteful number, since it uses less digits than its factorization.

21003213111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45478.

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 21003213111 its reverse (11131230012), we get a palindrome (32134443123).

The spelling of 21003213111 in words is "twenty-one billion, three million, two hundred thirteen thousand, one hundred eleven".