21033011231 has 8 divisors (see below), whose sum is σ = 21604324224. Its totient is φ = 20461848480.

The previous prime is 21033011213. The next prime is 21033011239. The reversal of 21033011231 is 13211033012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21033011231 is a prime.

It is a super-2 number, since 2×21033011231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21033011239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 282821 + ... + 349361.

It is an arithmetic number, because the mean of its divisors is an integer number (2700540528).

Almost surely, 2^21033011231 is an apocalyptic number.

21033011231 is a deficient number, since it is larger than the sum of its proper divisors (571312993).

21033011231 is an equidigital number, since it uses as much as digits as its factorization.

21033011231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75121.

The product of its (nonzero) digits is 108, while the sum is 17.

Adding to 21033011231 its reverse (13211033012), we get a palindrome (34244044243).

The spelling of 21033011231 in words is "twenty-one billion, thirty-three million, eleven thousand, two hundred thirty-one".