21566670701206 has 64 divisors (see below), whose sum is σ = 33719174112960. Its totient is φ = 10337278371840.

The previous prime is 21566670701183. The next prime is 21566670701267. The reversal of 21566670701206 is 60210707666512.

It is a self number, because there is not a number n which added to its sum of digits gives 21566670701206.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5520005905 + ... + 5520009811.

It is an arithmetic number, because the mean of its divisors is an integer number (526862095515).

Almost surely, 2^{21566670701206} is an apocalyptic number.

21566670701206 is a deficient number, since it is larger than the sum of its proper divisors (12152503411754).

21566670701206 is a wasteful number, since it uses less digits than its factorization.

21566670701206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7249.

The product of its (nonzero) digits is 1270080, while the sum is 49.

The spelling of 21566670701206 in words is "twenty-one trillion, five hundred sixty-six billion, six hundred seventy million, seven hundred one thousand, two hundred six".