160666515561 has 4 divisors (see below), whose sum is σ = 214222020752. Its totient is φ = 107111010372.

The previous prime is 160666515557. The next prime is 160666515599. The reversal of 160666515561 is 165515666061.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 160666515561 - 2² = 160666515557 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 160666515561.

It is not an unprimeable number, because it can be changed into a prime (160666515511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26777752591 + ... + 26777752596.

It is an arithmetic number, because the mean of its divisors is an integer number (53555505188).

Almost surely, 2^160666515561 is an apocalyptic number.

It is an amenable number.

160666515561 is a deficient number, since it is larger than the sum of its proper divisors (53555505191).

160666515561 is an equidigital number, since it uses as much as digits as its factorization.

160666515561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53555505190.

The product of its (nonzero) digits is 972000, while the sum is 48.

The spelling of 160666515561 in words is "one hundred sixty billion, six hundred sixty-six million, five hundred fifteen thousand, five hundred sixty-one".