21813818437213 has 8 divisors (see below), whose sum is σ = 24350308953696. Its totient is φ = 19369563939600.

The previous prime is 21813818437183. The next prime is 21813818437217. The reversal of 21813818437213 is 31273481831812.

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 21813818437213 - 2¹⁷ = 21813818306141 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21813818437217) 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, 23059004218 + ... + 23059005163.

It is an arithmetic number, because the mean of its divisors is an integer number (3043788619212).

Almost surely, 2^{21813818437213} is an apocalyptic number.

It is an amenable number.

21813818437213 is a deficient number, since it is larger than the sum of its proper divisors (2536490516483).

21813818437213 is a wasteful number, since it uses less digits than its factorization.

21813818437213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46118009435.

The product of its digits is 1548288, while the sum is 52.

The spelling of 21813818437213 in words is "twenty-one trillion, eight hundred thirteen billion, eight hundred eighteen million, four hundred thirty-seven thousand, two hundred thirteen".