17990894618 has 4 divisors (see below), whose sum is σ = 26986341930. Its totient is φ = 8995447308.

The previous prime is 17990894599. The next prime is 17990894627. The reversal of 17990894618 is 81649809971.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81649809971 = 7561 ⋅10798811.

It can be written as a sum of positive squares in only one way, i.e., 17489269009 + 501625609 = 132247^2 + 22397^2 .

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 4497723653 + ... + 4497723656.

Almost surely, 2^17990894618 is an apocalyptic number.

17990894618 is a deficient number, since it is larger than the sum of its proper divisors (8995447312).

17990894618 is an equidigital number, since it uses as much as digits as its factorization.

17990894618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8995447311.

The product of its (nonzero) digits is 7838208, while the sum is 62.

The spelling of 17990894618 in words is "seventeen billion, nine hundred ninety million, eight hundred ninety-four thousand, six hundred eighteen".