21111213433 has 6 divisors (see below), whose sum is σ = 21864289694. Its totient is φ = 20383239744.

The previous prime is 21111213407. The next prime is 21111213437. The reversal of 21111213433 is 33431211112.

It can be written as a sum of positive squares in 3 ways, for example, as 6877053184 + 14234160249 = 82928^2 + 119307^2 .

It is not a de Polignac number, because 21111213433 - 2⁵ = 21111213401 is a prime.

It is a super-2 number, since 2×21111213433² (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 (21111213437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12550416 + ... + 12552097.

Almost surely, 2^21111213433 is an apocalyptic number.

It is an amenable number.

21111213433 is a deficient number, since it is larger than the sum of its proper divisors (753076261).

21111213433 is an equidigital number, since it uses as much as digits as its factorization.

21111213433 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25102571 (or 25102542 counting only the distinct ones).

The product of its digits is 432, while the sum is 22.

Adding to 21111213433 its reverse (33431211112), we get a palindrome (54542424545).

The spelling of 21111213433 in words is "twenty-one billion, one hundred eleven million, two hundred thirteen thousand, four hundred thirty-three".