18373649 has 4 divisors (see below), whose sum is σ = 20998464. Its totient is φ = 15748836.

The previous prime is 18373631. The next prime is 18373657. The reversal of 18373649 is 94637381.

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: 94637381 = 1481 ⋅63901.

It is a cyclic number.

It is not a de Polignac number, because 18373649 - 2¹² = 18369553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18363649) 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, 1312397 + ... + 1312410.

It is an arithmetic number, because the mean of its divisors is an integer number (5249616).

Almost surely, 2^18373649 is an apocalyptic number.

It is an amenable number.

18373649 is a deficient number, since it is larger than the sum of its proper divisors (2624815).

18373649 is an equidigital number, since it uses as much as digits as its factorization.

18373649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2624814.

The product of its digits is 108864, while the sum is 41.

The square root of 18373649 is about 4286.4494631338. The cubic root of 18373649 is about 263.8751370431.

The spelling of 18373649 in words is "eighteen million, three hundred seventy-three thousand, six hundred forty-nine".