18505440432 has 120 divisors (see below), whose sum is σ = 52658256144. Its totient is φ = 6065528832.

The previous prime is 18505440427. The next prime is 18505440461. The reversal of 18505440432 is 23404450581.

It is a happy number.

18505440432 is a `hidden beast` number, since 1 + 85 + 0 + 544 + 0 + 4 + 32 = 666.

It is a super-3 number, since 3×18505440432³ (a number of 32 digits) contains 333 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3708243 + ... + 3713229.

Almost surely, 2^18505440432 is an apocalyptic number.

18505440432 is a gapful number since it is divisible by the number (12) 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 18505440432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26329128072).

18505440432 is an abundant number, since it is smaller than the sum of its proper divisors (34152815712).

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

18505440432 is a wasteful number, since it uses less digits than its factorization.

18505440432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5427 (or 5418 counting only the distinct ones).

The product of its (nonzero) digits is 76800, while the sum is 36.

The spelling of 18505440432 in words is "eighteen billion, five hundred five million, four hundred forty thousand, four hundred thirty-two".