18075661 has 4 divisors (see below), whose sum is σ = 18088000. Its totient is φ = 18063324.

The previous prime is 18075649. The next prime is 18075689. The reversal of 18075661 is 16657081.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18075661 - 2¹¹ = 18073613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18075611) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3621 + ... + 7018.

It is an arithmetic number, because the mean of its divisors is an integer number (4522000).

Almost surely, 2^18075661 is an apocalyptic number.

It is an amenable number.

18075661 is a deficient number, since it is larger than the sum of its proper divisors (12339).

18075661 is a wasteful number, since it uses less digits than its factorization.

18075661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12338.

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 18075661 is about 4251.5480709972. The cubic root of 18075661 is about 262.4408259663.

The spelling of 18075661 in words is "eighteen million, seventy-five thousand, six hundred sixty-one".