18196566 has 48 divisors (see below), whose sum is σ = 39794688. Its totient is φ = 5540400.

The previous prime is 18196561. The next prime is 18196571. The reversal of 18196566 is 66569181.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (18196561) and next prime (18196571).

It is a super-2 number, since 2×18196566² = 662230028384712, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18196561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 67011 + ... + 67281.

It is an arithmetic number, because the mean of its divisors is an integer number (829056).

Almost surely, 2^18196566 is an apocalyptic number.

18196566 is an abundant number, since it is smaller than the sum of its proper divisors (21598122).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18196566 is a wasteful number, since it uses less digits than its factorization.

18196566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 345 (or 326 counting only the distinct ones).

The product of its digits is 77760, while the sum is 42.

The square root of 18196566 is about 4265.7433115461. The cubic root of 18196566 is about 263.0246667337.

It can be divided in two parts, 1819 and 6566, that added together give a triangular number (8385 = T₁₂₉).

The spelling of 18196566 in words is "eighteen million, one hundred ninety-six thousand, five hundred sixty-six".