21601620666706 has 8 divisors (see below), whose sum is σ = 32405921540784. Its totient is φ = 10799646819780.

The previous prime is 21601620666701. The next prime is 21601620666797. The reversal of 21601620666706 is 60766602610612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21601620666706.

It is not an unprimeable number, because it can be changed into a prime (21601620666701) 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, 581733580 + ... + 581770711.

It is an arithmetic number, because the mean of its divisors is an integer number (4050740192598).

Almost surely, 2^{21601620666706} is an apocalyptic number.

21601620666706 is a deficient number, since it is larger than the sum of its proper divisors (10804300874078).

21601620666706 is a wasteful number, since it uses less digits than its factorization.

21601620666706 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1163513576.

The product of its (nonzero) digits is 1306368, while the sum is 49.

The spelling of 21601620666706 in words is "twenty-one trillion, six hundred one billion, six hundred twenty million, six hundred sixty-six thousand, seven hundred six".