18007223904 has 72 divisors (see below), whose sum is σ = 51275264040. Its totient is φ = 5994528768.

The previous prime is 18007223893. The next prime is 18007223981. The reversal of 18007223904 is 40932270081.

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-2 number, since 2×18007223904² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 180819 + ... + 262125.

It is an arithmetic number, because the mean of its divisors is an integer number (712156445).

Almost surely, 2^18007223904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18007223904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25637632020).

18007223904 is an abundant number, since it is smaller than the sum of its proper divisors (33268040136).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18007223904 is a wasteful number, since it uses less digits than its factorization.

18007223904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82092 (or 82081 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

Adding to 18007223904 its reverse (40932270081), we get a palindrome (58939493985).

The spelling of 18007223904 in words is "eighteen billion, seven million, two hundred twenty-three thousand, nine hundred four".