21766317603 has 16 divisors (see below), whose sum is σ = 29323575936. Its totient is φ = 14360252480.

The previous prime is 21766317593. The next prime is 21766317611. The reversal of 21766317603 is 30671366712.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21766317603 - 2¹² = 21766313507 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21766317803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 276775 + ... + 346607.

It is an arithmetic number, because the mean of its divisors is an integer number (1832723496).

Almost surely, 2^21766317603 is an apocalyptic number.

21766317603 is a deficient number, since it is larger than the sum of its proper divisors (7557258333).

21766317603 is a wasteful number, since it uses less digits than its factorization.

21766317603 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70914.

The product of its (nonzero) digits is 190512, while the sum is 42.

The spelling of 21766317603 in words is "twenty-one billion, seven hundred sixty-six million, three hundred seventeen thousand, six hundred three".