18486941721 has 32 divisors (see below), whose sum is σ = 25882926720. Its totient is φ = 11721024000.

The previous prime is 18486941719. The next prime is 18486941741. The reversal of 18486941721 is 12714968481.

It is not a de Polignac number, because 18486941721 - 2¹ = 18486941719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18486941741) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6482946 + ... + 6485796.

It is an arithmetic number, because the mean of its divisors is an integer number (808841460).

Almost surely, 2^18486941721 is an apocalyptic number.

It is an amenable number.

18486941721 is a deficient number, since it is larger than the sum of its proper divisors (7395984999).

18486941721 is a wasteful number, since it uses less digits than its factorization.

18486941721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3977.

The product of its digits is 774144, while the sum is 51.

The spelling of 18486941721 in words is "eighteen billion, four hundred eighty-six million, nine hundred forty-one thousand, seven hundred twenty-one".