163706987618 has 4 divisors (see below), whose sum is σ = 245560481430. Its totient is φ = 81853493808.

The previous prime is 163706987569. The next prime is 163706987657. The reversal of 163706987618 is 816789607361.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 129691456129 + 34015531489 = 360127^2 + 184433^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40926746903 + ... + 40926746906.

Almost surely, 2^163706987618 is an apocalyptic number.

163706987618 is a deficient number, since it is larger than the sum of its proper divisors (81853493812).

163706987618 is an equidigital number, since it uses as much as digits as its factorization.

163706987618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81853493811.

The product of its (nonzero) digits is 18289152, while the sum is 62.

The spelling of 163706987618 in words is "one hundred sixty-three billion, seven hundred six million, nine hundred eighty-seven thousand, six hundred eighteen".