18735721396 has 12 divisors (see below), whose sum is σ = 37471442848. Its totient is φ = 8029594872.

The previous prime is 18735721391. The next prime is 18735721397. The reversal of 18735721396 is 69312753781.

18735721396 is an admirable number.

It is a hoax number, since the sum of its digits (52) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18735721391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 334566426 + ... + 334566481.

Almost surely, 2^18735721396 is an apocalyptic number.

It is an amenable number.

18735721396 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18735721396 is a wasteful number, since it uses less digits than its factorization.

18735721396 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 669132918 (or 669132916 counting only the distinct ones).

The product of its digits is 1905120, while the sum is 52.

The spelling of 18735721396 in words is "eighteen billion, seven hundred thirty-five million, seven hundred twenty-one thousand, three hundred ninety-six".