21216020066113 has 4 divisors (see below), whose sum is σ = 21709415881648. Its totient is φ = 20722624250580.

The previous prime is 21216020066093. The next prime is 21216020066141. The reversal of 21216020066113 is 31166002061212.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21216020066113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21216020066413) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 246697907703 + ... + 246697907788.

It is an arithmetic number, because the mean of its divisors is an integer number (5427353970412).

Almost surely, 2^{21216020066113} is an apocalyptic number.

It is an amenable number.

21216020066113 is a deficient number, since it is larger than the sum of its proper divisors (493395815535).

21216020066113 is an equidigital number, since it uses as much as digits as its factorization.

21216020066113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 493395815534.

The product of its (nonzero) digits is 5184, while the sum is 31.

The spelling of 21216020066113 in words is "twenty-one trillion, two hundred sixteen billion, twenty million, sixty-six thousand, one hundred thirteen".