18418256237 has 4 divisors (see below), whose sum is σ = 18448599936. Its totient is φ = 18387912540.

The previous prime is 18418256203. The next prime is 18418256291. The reversal of 18418256237 is 73265281481.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18418256237 - 2¹² = 18418252141 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18418256191 and 18418256200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18418256137) 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, 15170939 + ... + 15172152.

It is an arithmetic number, because the mean of its divisors is an integer number (4612149984).

Almost surely, 2^18418256237 is an apocalyptic number.

It is an amenable number.

18418256237 is a deficient number, since it is larger than the sum of its proper divisors (30343699).

18418256237 is an equidigital number, since it uses as much as digits as its factorization.

18418256237 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30343698.

The product of its digits is 645120, while the sum is 47.

The spelling of 18418256237 in words is "eighteen billion, four hundred eighteen million, two hundred fifty-six thousand, two hundred thirty-seven".