21943736512511 has 64 divisors (see below), whose sum is σ = 25563205850112. Its totient is φ = 18657475200000.

The previous prime is 21943736512501. The next prime is 21943736512531. The reversal of 21943736512511 is 11521563734912.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21943736512511 - 2⁶ = 21943736512447 is a prime.

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 21943736512511.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21943736512501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 220120700 + ... + 220220366.

It is an arithmetic number, because the mean of its divisors is an integer number (399425091408).

Almost surely, 2^{21943736512511} is an apocalyptic number.

21943736512511 is a deficient number, since it is larger than the sum of its proper divisors (3619469337601).

21943736512511 is a wasteful number, since it uses less digits than its factorization.

21943736512511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99984.

The product of its digits is 1360800, while the sum is 50.

The spelling of 21943736512511 in words is "twenty-one trillion, nine hundred forty-three billion, seven hundred thirty-six million, five hundred twelve thousand, five hundred eleven".