21608070664 has 16 divisors (see below), whose sum is σ = 41070135420. Its totient is φ = 10656034560.

The previous prime is 21608070629. The next prime is 21608070667. The reversal of 21608070664 is 46607080612.

It can be written as a sum of positive squares in 2 ways, for example, as 21182473764 + 425596900 = 145542^2 + 20630^2 .

It is not an unprimeable number, because it can be changed into a prime (21608070667) 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 3 ways as a sum of consecutive naturals, for example, 18499477 + ... + 18500644.

Almost surely, 2^21608070664 is an apocalyptic number.

It is an amenable number.

21608070664 is a deficient number, since it is larger than the sum of its proper divisors (19462064756).

21608070664 is a wasteful number, since it uses less digits than its factorization.

21608070664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37000200 (or 37000196 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 40.

The spelling of 21608070664 in words is "twenty-one billion, six hundred eight million, seventy thousand, six hundred sixty-four".