18233949 has 4 divisors (see below), whose sum is σ = 24311936. Its totient is φ = 12155964.

The previous prime is 18233947. The next prime is 18233951. The reversal of 18233949 is 94933281.

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: 94933281 = 3 ⋅31644427.

It is an interprime number because it is at equal distance from previous prime (18233947) and next prime (18233951).

It is not a de Polignac number, because 18233949 - 2¹ = 18233947 is a prime.

It is a super-2 number, since 2×18233949² = 664953792269202, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18233947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3038989 + ... + 3038994.

It is an arithmetic number, because the mean of its divisors is an integer number (6077984).

Almost surely, 2^18233949 is an apocalyptic number.

It is an amenable number.

18233949 is a deficient number, since it is larger than the sum of its proper divisors (6077987).

18233949 is an equidigital number, since it uses as much as digits as its factorization.

18233949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6077986.

The product of its digits is 46656, while the sum is 39.

The square root of 18233949 is about 4270.1228319569. The cubic root of 18233949 is about 263.2046626992.

The spelling of 18233949 in words is "eighteen million, two hundred thirty-three thousand, nine hundred forty-nine".