21213544061243 has 8 divisors (see below), whose sum is σ = 21324885483216. Its totient is φ = 21102304557600.

The previous prime is 21213544061207. The next prime is 21213544061263. The reversal of 21213544061243 is 34216044531212.

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 21213544061243 - 2⁸ = 21213544060987 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21213544061197 and 21213544061206.

It is not an unprimeable number, because it can be changed into a prime (21213544061263) 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, 25062188 + ... + 25894793.

It is an arithmetic number, because the mean of its divisors is an integer number (2665610685402).

Almost surely, 2^{21213544061243} is an apocalyptic number.

21213544061243 is a deficient number, since it is larger than the sum of its proper divisors (111341421973).

21213544061243 is a wasteful number, since it uses less digits than its factorization.

21213544061243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50959165.

The product of its (nonzero) digits is 138240, while the sum is 38.

Adding to 21213544061243 its reverse (34216044531212), we get a palindrome (55429588592455).

The spelling of 21213544061243 in words is "twenty-one trillion, two hundred thirteen billion, five hundred forty-four million, sixty-one thousand, two hundred forty-three".