161006618 has 4 divisors (see below), whose sum is σ = 241509930. Its totient is φ = 80503308.

The previous prime is 161006611. The next prime is 161006621. The reversal of 161006618 is 816600161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 816600161 = 13 ⋅62815397.

It can be written as a sum of positive squares in only one way, i.e., 160098409 + 908209 = 12653^2 + 953^2 .

It is not an unprimeable number, because it can be changed into a prime (161006611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40251653 + ... + 40251656.

Almost surely, 2^161006618 is an apocalyptic number.

161006618 is a deficient number, since it is larger than the sum of its proper divisors (80503312).

161006618 is an equidigital number, since it uses as much as digits as its factorization.

161006618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80503311.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 161006618 is about 12688.8383235031. The cubic root of 161006618 is about 544.0196364199.

Adding to 161006618 its reverse (816600161), we get a palindrome (977606779).

The spelling of 161006618 in words is "one hundred sixty-one million, six thousand, six hundred eighteen".