18735721403 has 8 divisors (see below), whose sum is σ = 22671797472. Its totient is φ = 15114531456.

The previous prime is 18735721397. The next prime is 18735721421. The reversal of 18735721403 is 30412753781.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18735721403 - 2⁴ = 18735721387 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18735721003) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78721400 + ... + 78721637.

It is an arithmetic number, because the mean of its divisors is an integer number (2833974684).

Almost surely, 2^18735721403 is an apocalyptic number.

18735721403 is a deficient number, since it is larger than the sum of its proper divisors (3936076069).

18735721403 is a wasteful number, since it uses less digits than its factorization.

18735721403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157443061.

The product of its (nonzero) digits is 141120, while the sum is 41.

The spelling of 18735721403 in words is "eighteen billion, seven hundred thirty-five million, seven hundred twenty-one thousand, four hundred three".