18630398 has 4 divisors (see below), whose sum is σ = 27945600. Its totient is φ = 9315198.

The previous prime is 18630397. The next prime is 18630449. The reversal of 18630398 is 89303681.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 89303681 = 37 ⋅2413613.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18630397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4657598 + ... + 4657601.

It is an arithmetic number, because the mean of its divisors is an integer number (6986400).

Almost surely, 2^18630398 is an apocalyptic number.

18630398 is a deficient number, since it is larger than the sum of its proper divisors (9315202).

18630398 is an equidigital number, since it uses as much as digits as its factorization.

18630398 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9315201.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 18630398 is about 4316.2944755890. The cubic root of 18630398 is about 265.0985654468.

The spelling of 18630398 in words is "eighteen million, six hundred thirty thousand, three hundred ninety-eight".