18641121682 has 4 divisors (see below), whose sum is σ = 27961682526. Its totient is φ = 9320560840.

The previous prime is 18641121679. The next prime is 18641121683. The reversal of 18641121682 is 28612114681.

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

It can be written as a sum of positive squares in only one way, i.e., 12292378641 + 6348743041 = 110871^2 + 79679^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (18641121683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4660280419 + ... + 4660280422.

Almost surely, 2^18641121682 is an apocalyptic number.

18641121682 is a deficient number, since it is larger than the sum of its proper divisors (9320560844).

18641121682 is an equidigital number, since it uses as much as digits as its factorization.

18641121682 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9320560843.

The product of its digits is 36864, while the sum is 40.

The spelling of 18641121682 in words is "eighteen billion, six hundred forty-one million, one hundred twenty-one thousand, six hundred eighty-two".