208145121066 has 32 divisors (see below), whose sum is σ = 469448374080. Its totient is φ = 68346157968.

The previous prime is 208145121001. The next prime is 208145121071. The reversal of 208145121066 is 660121541802.

It is a happy number.

208145121066 is a `hidden beast` number, since 2 + 0 + 81 + 4 + 512 + 1 + 0 + 66 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 208145121066.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28761601 + ... + 28768836.

It is an arithmetic number, because the mean of its divisors is an integer number (14670261690).

Almost surely, 2^208145121066 is an apocalyptic number.

208145121066 is an abundant number, since it is smaller than the sum of its proper divisors (261303253014).

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

208145121066 is a wasteful number, since it uses less digits than its factorization.

208145121066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57530515 (or 57530509 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

Adding to 208145121066 its reverse (660121541802), we get a palindrome (868266662868).

The spelling of 208145121066 in words is "two hundred eight billion, one hundred forty-five million, one hundred twenty-one thousand, sixty-six".