18212018761 has 4 divisors (see below), whose sum is σ = 18252580500. Its totient is φ = 18171457024.

The previous prime is 18212018743. The next prime is 18212018813. The reversal of 18212018761 is 16781021281.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4418925625 + 13793093136 = 66475^2 + 117444^2 .

It is a cyclic number.

It is not a de Polignac number, because 18212018761 - 2¹⁷ = 18211887689 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18212018761.

It is not an unprimeable number, because it can be changed into a prime (18212018731) 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, 20280196 + ... + 20281093.

It is an arithmetic number, because the mean of its divisors is an integer number (4563145125).

Almost surely, 2^18212018761 is an apocalyptic number.

It is an amenable number.

18212018761 is a deficient number, since it is larger than the sum of its proper divisors (40561739).

18212018761 is an equidigital number, since it uses as much as digits as its factorization.

18212018761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40561738.

The product of its (nonzero) digits is 10752, while the sum is 37.

The spelling of 18212018761 in words is "eighteen billion, two hundred twelve million, eighteen thousand, seven hundred sixty-one".