18630649387 has 4 divisors (see below), whose sum is σ = 21292170736. Its totient is φ = 15969128040.

The previous prime is 18630649379. The next prime is 18630649391. The reversal of 18630649387 is 78394603681.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 18630649387 - 2³ = 18630649379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18630649327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1330760664 + ... + 1330760677.

It is an arithmetic number, because the mean of its divisors is an integer number (5323042684).

Almost surely, 2^18630649387 is an apocalyptic number.

18630649387 is a deficient number, since it is larger than the sum of its proper divisors (2661521349).

18630649387 is an equidigital number, since it uses as much as digits as its factorization.

18630649387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2661521348.

The product of its (nonzero) digits is 5225472, while the sum is 55.

The spelling of 18630649387 in words is "eighteen billion, six hundred thirty million, six hundred forty-nine thousand, three hundred eighty-seven".