18670203649 has 4 divisors (see below), whose sum is σ = 18673168320. Its totient is φ = 18667238980.

The previous prime is 18670203647. The next prime is 18670203653. The reversal of 18670203649 is 94630207681.

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: 94630207681 = 76507 ⋅1236883.

It is a cyclic number.

It is not a de Polignac number, because 18670203649 - 2¹ = 18670203647 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18670203599 and 18670203608.

It is not an unprimeable number, because it can be changed into a prime (18670203647) 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, 1472869 + ... + 1485490.

It is an arithmetic number, because the mean of its divisors is an integer number (4668292080).

Almost surely, 2^18670203649 is an apocalyptic number.

It is an amenable number.

18670203649 is a deficient number, since it is larger than the sum of its proper divisors (2964671).

18670203649 is an equidigital number, since it uses as much as digits as its factorization.

18670203649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2964670.

The product of its (nonzero) digits is 435456, while the sum is 46.

The spelling of 18670203649 in words is "eighteen billion, six hundred seventy million, two hundred three thousand, six hundred forty-nine".