18012404399 has 4 divisors (see below), whose sum is σ = 19649895720. Its totient is φ = 16374913080.

The previous prime is 18012404341. The next prime is 18012404413. The reversal of 18012404399 is 99340421081.

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 18012404399 - 2¹⁶ = 18012338863 is a prime.

It is a super-2 number, since 2×18012404399² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18012404699) 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, 818745644 + ... + 818745665.

It is an arithmetic number, because the mean of its divisors is an integer number (4912473930).

Almost surely, 2^18012404399 is an apocalyptic number.

18012404399 is a deficient number, since it is larger than the sum of its proper divisors (1637491321).

18012404399 is a wasteful number, since it uses less digits than its factorization.

18012404399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1637491320.

The product of its (nonzero) digits is 62208, while the sum is 41.

The spelling of 18012404399 in words is "eighteen billion, twelve million, four hundred four thousand, three hundred ninety-nine".