166605161561111 has 64 divisors (see below), whose sum is σ = 210316574146560. Its totient is φ = 128460738032640.

The previous prime is 166605161561053. The next prime is 166605161561123. The reversal of 166605161561111 is 111165161506661.

It is not a de Polignac number, because 166605161561111 - 2¹⁴ = 166605161544727 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166605161561141) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 946279490 + ... + 946455536.

It is an arithmetic number, because the mean of its divisors is an integer number (3286196471040).

Almost surely, 2^{166605161561111} is an apocalyptic number.

166605161561111 is a deficient number, since it is larger than the sum of its proper divisors (43711412585449).

166605161561111 is a wasteful number, since it uses less digits than its factorization.

166605161561111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177064.

The product of its (nonzero) digits is 194400, while the sum is 47.

The spelling of 166605161561111 in words is "one hundred sixty-six trillion, six hundred five billion, one hundred sixty-one million, five hundred sixty-one thousand, one hundred eleven".