18196887715 has 4 divisors (see below), whose sum is σ = 21836265264. Its totient is φ = 14557510168.

The previous prime is 18196887701. The next prime is 18196887719. The reversal of 18196887715 is 51778869181.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18196887715 - 2¹³ = 18196879523 is a prime.

It is a super-2 number, since 2×18196887715² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18196887719) 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, 1819688767 + ... + 1819688776.

It is an arithmetic number, because the mean of its divisors is an integer number (5459066316).

Almost surely, 2^18196887715 is an apocalyptic number.

18196887715 is a deficient number, since it is larger than the sum of its proper divisors (3639377549).

18196887715 is an equidigital number, since it uses as much as digits as its factorization.

18196887715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3639377548.

The product of its digits is 6773760, while the sum is 61.

The spelling of 18196887715 in words is "eighteen billion, one hundred ninety-six million, eight hundred eighty-seven thousand, seven hundred fifteen".