1606436618 has 4 divisors (see below), whose sum is σ = 2409654930. Its totient is φ = 803218308.

The previous prime is 1606436609. The next prime is 1606436669. The reversal of 1606436618 is 8166346061.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8166346061 = 46279 ⋅176459.

It can be written as a sum of positive squares in only one way, i.e., 1569506689 + 36929929 = 39617^2 + 6077^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 401609153 + ... + 401609156.

Almost surely, 2^1606436618 is an apocalyptic number.

1606436618 is a deficient number, since it is larger than the sum of its proper divisors (803218312).

1606436618 is an equidigital number, since it uses as much as digits as its factorization.

1606436618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 803218311.

The product of its (nonzero) digits is 124416, while the sum is 41.

The square root of 1606436618 is about 40080.3769692851. The cubic root of 1606436618 is about 1171.1733955769.

The spelling of 1606436618 in words is "one billion, six hundred six million, four hundred thirty-six thousand, six hundred eighteen".