18312149 has 4 divisors (see below), whose sum is σ = 18342636. Its totient is φ = 18281664.

The previous prime is 18312131. The next prime is 18312167. The reversal of 18312149 is 94121381.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (18312131) and next prime (18312167).

It can be written as a sum of positive squares in 2 ways, for example, as 7879249 + 10432900 = 2807^2 + 3230^2 .

It is a cyclic number.

It is not a de Polignac number, because 18312149 - 2⁸ = 18311893 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 (18012149) 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, 14324 + ... + 15549.

It is an arithmetic number, because the mean of its divisors is an integer number (4585659).

Almost surely, 2^18312149 is an apocalyptic number.

It is an amenable number.

18312149 is a deficient number, since it is larger than the sum of its proper divisors (30487).

18312149 is an equidigital number, since it uses as much as digits as its factorization.

18312149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30486.

The product of its digits is 1728, while the sum is 29.

The square root of 18312149 is about 4279.2696806815. The cubic root of 18312149 is about 263.5803949903.

The spelling of 18312149 in words is "eighteen million, three hundred twelve thousand, one hundred forty-nine".