18161684542 has 4 divisors (see below), whose sum is σ = 27242526816. Its totient is φ = 9080842270.

The previous prime is 18161684501. The next prime is 18161684561. The reversal of 18161684542 is 24548616181.

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

It is a junction number, because it is equal to n+sod(n) for n = 18161684492 and 18161684501.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4540421134 + ... + 4540421137.

It is an arithmetic number, because the mean of its divisors is an integer number (6810631704).

Almost surely, 2^18161684542 is an apocalyptic number.

18161684542 is a deficient number, since it is larger than the sum of its proper divisors (9080842274).

18161684542 is an equidigital number, since it uses as much as digits as its factorization.

18161684542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9080842273.

The product of its digits is 368640, while the sum is 46.

The spelling of 18161684542 in words is "eighteen billion, one hundred sixty-one million, six hundred eighty-four thousand, five hundred forty-two".