206666688646 has 32 divisors (see below), whose sum is σ = 373643394048. Its totient is φ = 84569485440.

The previous prime is 206666688611. The next prime is 206666688649. The reversal of 206666688646 is 646886666602.

It is a super-2 number, since 2×206666688646² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206666688649) 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, 12004110 + ... + 12021313.

It is an arithmetic number, because the mean of its divisors is an integer number (11676356064).

Almost surely, 2^206666688646 is an apocalyptic number.

206666688646 is a deficient number, since it is larger than the sum of its proper divisors (166976705402).

206666688646 is a wasteful number, since it uses less digits than its factorization.

206666688646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24025476.

The product of its (nonzero) digits is 143327232, while the sum is 64.

The spelling of 206666688646 in words is "two hundred six billion, six hundred sixty-six million, six hundred eighty-eight thousand, six hundred forty-six".