21316666065103 has 4 divisors (see below), whose sum is σ = 21333177813928. Its totient is φ = 21300154316280.

The previous prime is 21316666065059. The next prime is 21316666065133. The reversal of 21316666065103 is 30156066661312.

It is a happy number.

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 21316666065103 - 2⁹ = 21316666064591 is a prime.

It is a super-2 number, since 2×21316666065103² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21316666065133) 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, 8255872476 + ... + 8255875057.

It is an arithmetic number, because the mean of its divisors is an integer number (5333294453482).

Almost surely, 2^{21316666065103} is an apocalyptic number.

21316666065103 is a deficient number, since it is larger than the sum of its proper divisors (16511748825).

21316666065103 is a wasteful number, since it uses less digits than its factorization.

21316666065103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16511748824.

The product of its (nonzero) digits is 699840, while the sum is 46.

It can be divided in two parts, 2131666 and 6065103, that added together give a square (8196769 = 2863²).

The spelling of 21316666065103 in words is "twenty-one trillion, three hundred sixteen billion, six hundred sixty-six million, sixty-five thousand, one hundred three".