18120534240 has 96 divisors (see below), whose sum is σ = 57290720256. Its totient is φ = 4814277120.

The previous prime is 18120534221. The next prime is 18120534283. The reversal of 18120534240 is 4243502181.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×18120534240² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 18120534198 and 18120534207.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 60429 + ... + 199731.

It is an arithmetic number, because the mean of its divisors is an integer number (596778336).

Almost surely, 2^18120534240 is an apocalyptic number.

18120534240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18120534240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28645360128).

18120534240 is an abundant number, since it is smaller than the sum of its proper divisors (39170186016).

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

18120534240 is a wasteful number, since it uses less digits than its factorization.

18120534240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139592 (or 139584 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 30.

The spelling of 18120534240 in words is "eighteen billion, one hundred twenty million, five hundred thirty-four thousand, two hundred forty".