21110533543 has 16 divisors (see below), whose sum is σ = 24098245632. Its totient is φ = 18317880000.

The previous prime is 21110533511. The next prime is 21110533559. The reversal of 21110533543 is 34533501112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21110533543 - 2⁵ = 21110533511 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21110533573) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 399133 + ... + 448918.

It is an arithmetic number, because the mean of its divisors is an integer number (1506140352).

Almost surely, 2^21110533543 is an apocalyptic number.

21110533543 is a deficient number, since it is larger than the sum of its proper divisors (2987712089).

21110533543 is a wasteful number, since it uses less digits than its factorization.

21110533543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 848166.

The product of its (nonzero) digits is 5400, while the sum is 28.

It can be divided in two parts, 2111053 and 3543, that added together give a triangular number (2114596 = T₂₀₅₆).

The spelling of 21110533543 in words is "twenty-one billion, one hundred ten million, five hundred thirty-three thousand, five hundred forty-three".