21602066661606 has 32 divisors (see below), whose sum is σ = 43534638056448. Its totient is φ = 7145606538720.

The previous prime is 21602066661601. The next prime is 21602066661607. The reversal of 21602066661606 is 60616666020612.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21602066661601) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 58393836 + ... + 58762608.

It is an arithmetic number, because the mean of its divisors is an integer number (1360457439264).

Almost surely, 2^{21602066661606} is an apocalyptic number.

21602066661606 is an abundant number, since it is smaller than the sum of its proper divisors (21932571394842).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21602066661606 is a wasteful number, since it uses less digits than its factorization.

21602066661606 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 443436.

The product of its (nonzero) digits is 1119744, while the sum is 48.

The spelling of 21602066661606 in words is "twenty-one trillion, six hundred two billion, sixty-six million, six hundred sixty-one thousand, six hundred six".