21208073679 has 48 divisors (see below), whose sum is σ = 34613173504. Its totient is φ = 12422937600.

The previous prime is 21208073659. The next prime is 21208073683. The reversal of 21208073679 is 97637080212.

It is not a de Polignac number, because 21208073679 - 2⁹ = 21208073167 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21208073659) 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 47 ways as a sum of consecutive naturals, for example, 173319 + ... + 269175.

Almost surely, 2^21208073679 is an apocalyptic number.

21208073679 is a deficient number, since it is larger than the sum of its proper divisors (13405099825).

21208073679 is a wasteful number, since it uses less digits than its factorization.

21208073679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95968 (or 95965 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 45.

The spelling of 21208073679 in words is "twenty-one billion, two hundred eight million, seventy-three thousand, six hundred seventy-nine".