18196985 has 4 divisors (see below), whose sum is σ = 21836388. Its totient is φ = 14557584.

The previous prime is 18196963. The next prime is 18196993. The reversal of 18196985 is 58969181.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58969181 = 73 ⋅807797.

It can be written as a sum of positive squares in 2 ways, for example, as 13920361 + 4276624 = 3731^2 + 2068^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18196985 is a prime.

It is a super-2 number, since 2×18196985² = 662260526180450, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1819694 + ... + 1819703.

It is an arithmetic number, because the mean of its divisors is an integer number (5459097).

Almost surely, 2^18196985 is an apocalyptic number.

It is an amenable number.

18196985 is a deficient number, since it is larger than the sum of its proper divisors (3639403).

18196985 is an equidigital number, since it uses as much as digits as its factorization.

18196985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3639402.

The product of its digits is 155520, while the sum is 47.

The square root of 18196985 is about 4265.7924234543. The cubic root of 18196985 is about 263.0266855485.

The spelling of 18196985 in words is "eighteen million, one hundred ninety-six thousand, nine hundred eighty-five".