21144033004231 has 4 divisors (see below), whose sum is σ = 21144069684864. Its totient is φ = 21143996323600.

The previous prime is 21144033004229. The next prime is 21144033004247. The reversal of 21144033004231 is 13240033044112.

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 21144033004231 - 2¹ = 21144033004229 is a prime.

It is a super-2 number, since 2×21144033004231² (a number of 27 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 21144033004231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21144033004261) 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, 17461630 + ... + 18633211.

It is an arithmetic number, because the mean of its divisors is an integer number (5286017421216).

Almost surely, 2^{21144033004231} is an apocalyptic number.

21144033004231 is a deficient number, since it is larger than the sum of its proper divisors (36680633).

21144033004231 is an equidigital number, since it uses as much as digits as its factorization.

21144033004231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36680632.

The product of its (nonzero) digits is 6912, while the sum is 28.

Adding to 21144033004231 its reverse (13240033044112), we get a palindrome (34384066048343).

The spelling of 21144033004231 in words is "twenty-one trillion, one hundred forty-four billion, thirty-three million, four thousand, two hundred thirty-one".