21613321371767 has 4 divisors (see below), whose sum is σ = 22750864601880. Its totient is φ = 20475778141656.

The previous prime is 21613321371751. The next prime is 21613321371787. The reversal of 21613321371767 is 76717312331612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21613321371767 - 2⁴ = 21613321371751 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 (21613321371787) 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, 568771615028 + ... + 568771615065.

It is an arithmetic number, because the mean of its divisors is an integer number (5687716150470).

Almost surely, 2^{21613321371767} is an apocalyptic number.

21613321371767 is a deficient number, since it is larger than the sum of its proper divisors (1137543230113).

21613321371767 is a wasteful number, since it uses less digits than its factorization.

21613321371767 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1137543230112.

The product of its digits is 1333584, while the sum is 50.

The spelling of 21613321371767 in words is "twenty-one trillion, six hundred thirteen billion, three hundred twenty-one million, three hundred seventy-one thousand, seven hundred sixty-seven".