161664836785 has 16 divisors (see below), whose sum is σ = 201717545472. Its totient is φ = 124246281600.

The previous prime is 161664836783. The next prime is 161664836797. The reversal of 161664836785 is 587638466161.

It is not a de Polignac number, because 161664836785 - 2¹ = 161664836783 is a prime.

It is a super-2 number, since 2×161664836785² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161664836783) 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, 3785331 + ... + 3827800.

It is an arithmetic number, because the mean of its divisors is an integer number (12607346592).

Almost surely, 2^161664836785 is an apocalyptic number.

It is an amenable number.

161664836785 is a deficient number, since it is larger than the sum of its proper divisors (40052708687).

161664836785 is a wasteful number, since it uses less digits than its factorization.

161664836785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7613304.

The product of its digits is 34836480, while the sum is 61.

The spelling of 161664836785 in words is "one hundred sixty-one billion, six hundred sixty-four million, eight hundred thirty-six thousand, seven hundred eighty-five".