161287618 has 16 divisors (see below), whose sum is σ = 263448000. Its totient is φ = 73764432.

The previous prime is 161287613. The next prime is 161287657. The reversal of 161287618 is 816782161.

It is a super-2 number, since 2×161287618² = 52027391440227848, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161287613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72078 + ... + 74281.

It is an arithmetic number, because the mean of its divisors is an integer number (16465500).

Almost surely, 2^161287618 is an apocalyptic number.

161287618 is a deficient number, since it is larger than the sum of its proper divisors (102160382).

161287618 is a wasteful number, since it uses less digits than its factorization.

161287618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146409.

The product of its digits is 32256, while the sum is 40.

The square root of 161287618 is about 12699.9062201262. The cubic root of 161287618 is about 544.3359395074.

The spelling of 161287618 in words is "one hundred sixty-one million, two hundred eighty-seven thousand, six hundred eighteen".