16642985 has 4 divisors (see below), whose sum is σ = 19971588. Its totient is φ = 13314384.

The previous prime is 16642981. The next prime is 16643023. The reversal of 16642985 is 58924661.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58924661 = 1877 ⋅31393.

It can be written as a sum of positive squares in 2 ways, for example, as 2347024 + 14295961 = 1532^2 + 3781^2 .

It is a cyclic number.

It is not a de Polignac number, because 16642985 - 2² = 16642981 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16642981) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 1664294 + ... + 1664303.

It is an arithmetic number, because the mean of its divisors is an integer number (4992897).

Almost surely, 2^16642985 is an apocalyptic number.

It is an amenable number.

16642985 is a deficient number, since it is larger than the sum of its proper divisors (3328603).

16642985 is an equidigital number, since it uses as much as digits as its factorization.

16642985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3328602.

The product of its digits is 103680, while the sum is 41.

The square root of 16642985 is about 4079.5814736318. The cubic root of 16642985 is about 255.3154368873.

The spelling of 16642985 in words is "sixteen million, six hundred forty-two thousand, nine hundred eighty-five".