18511720996 has 12 divisors (see below), whose sum is σ = 32926586140. Its totient is φ = 9104124960.

The previous prime is 18511720991. The next prime is 18511721009. The reversal of 18511720996 is 69902711581.

It can be written as a sum of positive squares in 2 ways, for example, as 6009350400 + 12502370596 = 77520^2 + 111814^2 .

It is not an unprimeable number, because it can be changed into a prime (18511720991) 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, 37933611 + ... + 37934098.

Almost surely, 2^18511720996 is an apocalyptic number.

It is an amenable number.

18511720996 is a deficient number, since it is larger than the sum of its proper divisors (14414865144).

18511720996 is a wasteful number, since it uses less digits than its factorization.

18511720996 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75867774 (or 75867772 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 49.

The spelling of 18511720996 in words is "eighteen billion, five hundred eleven million, seven hundred twenty thousand, nine hundred ninety-six".