21144243252011 has 8 divisors (see below), whose sum is σ = 23501663169264. Its totient is φ = 18859359332320.

The previous prime is 21144243252007. The next prime is 21144243252031. The reversal of 21144243252011 is 11025234244112.

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

It is a cyclic number.

It is not a de Polignac number, because 21144243252011 - 2² = 21144243252007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21144243252031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18133998776 + ... + 18133999941.

It is an arithmetic number, because the mean of its divisors is an integer number (2937707896158).

Almost surely, 2^{21144243252011} is an apocalyptic number.

21144243252011 is a deficient number, since it is larger than the sum of its proper divisors (2357419917253).

21144243252011 is a wasteful number, since it uses less digits than its factorization.

21144243252011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36267998781.

The product of its (nonzero) digits is 15360, while the sum is 32.

Adding to 21144243252011 its reverse (11025234244112), we get a palindrome (32169477496123).

The spelling of 21144243252011 in words is "twenty-one trillion, one hundred forty-four billion, two hundred forty-three million, two hundred fifty-two thousand, eleven".