18113961 has 4 divisors (see below), whose sum is σ = 24151952. Its totient is φ = 12075972.

The previous prime is 18113957. The next prime is 18113971. The reversal of 18113961 is 16931181.

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, and also an emirpimes, since its reverse is a distinct semiprime: 16931181 = 3 ⋅5643727.

It is not a de Polignac number, because 18113961 - 2² = 18113957 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18113971) 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 3 ways as a sum of consecutive naturals, for example, 3018991 + ... + 3018996.

It is an arithmetic number, because the mean of its divisors is an integer number (6037988).

Almost surely, 2^18113961 is an apocalyptic number.

It is an amenable number.

18113961 is a deficient number, since it is larger than the sum of its proper divisors (6037991).

18113961 is an equidigital number, since it uses as much as digits as its factorization.

18113961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6037990.

The product of its digits is 1296, while the sum is 30.

The square root of 18113961 is about 4256.0499292184. The cubic root of 18113961 is about 262.6260546506.

The spelling of 18113961 in words is "eighteen million, one hundred thirteen thousand, nine hundred sixty-one".