21213560340541 has 8 divisors (see below), whose sum is σ = 21226915417400. Its totient is φ = 21200208330240.

The previous prime is 21213560340527. The next prime is 21213560340547. The reversal of 21213560340541 is 14504306531212.

It can be written as a sum of positive squares in 4 ways, for example, as 13475844534916 + 7737715805625 = 3670946^2 + 2781675^2 .

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 21213560340541 - 2⁵ = 21213560340509 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 21213560340541.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21213560340547) 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, 13152565 + ... + 14677093.

It is an arithmetic number, because the mean of its divisors is an integer number (2653364427175).

Almost surely, 2^{21213560340541} is an apocalyptic number.

It is an amenable number.

21213560340541 is a deficient number, since it is larger than the sum of its proper divisors (13355076859).

21213560340541 is a wasteful number, since it uses less digits than its factorization.

21213560340541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1533279.

The product of its (nonzero) digits is 86400, while the sum is 37.

Adding to 21213560340541 its reverse (14504306531212), we get a palindrome (35717866871753).

The spelling of 21213560340541 in words is "twenty-one trillion, two hundred thirteen billion, five hundred sixty million, three hundred forty thousand, five hundred forty-one".