16642618 has 4 divisors (see below), whose sum is σ = 24963930. Its totient is φ = 8321308.

The previous prime is 16642601. The next prime is 16642621. The reversal of 16642618 is 81624661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81624661 = 919 ⋅88819.

It can be written as a sum of positive squares in only one way, i.e., 13520329 + 3122289 = 3677^2 + 1767^2 .

It is a super-4 number, since 4×16642618⁴ (a number of 30 digits) contains 4444 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4160653 + ... + 4160656.

Almost surely, 2^16642618 is an apocalyptic number.

16642618 is a deficient number, since it is larger than the sum of its proper divisors (8321312).

16642618 is an equidigital number, since it uses as much as digits as its factorization.

16642618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8321311.

The product of its digits is 13824, while the sum is 34.

The square root of 16642618 is about 4079.5364932796. The cubic root of 16642618 is about 255.3135601916.

The spelling of 16642618 in words is "sixteen million, six hundred forty-two thousand, six hundred eighteen".