18128240640 has 340 divisors, whose sum is σ = 65087761464. Its totient is φ = 4827119616.

The previous prime is 18128240621. The next prime is 18128240659. The reversal of 18128240640 is 4604282181.

18128240640 is a `hidden beast` number, since 1 + 8 + 1 + 2 + 8 + 2 + 4 + 0 + 640 = 666.

It is an interprime number because it is at equal distance from previous prime (18128240621) and next prime (18128240659).

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

It is a junction number, because it is equal to n+sod(n) for n = 18128240595 and 18128240604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 26541739 + ... + 26542421.

Almost surely, 2^18128240640 is an apocalyptic number.

18128240640 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 18128240640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32543880732).

18128240640 is an abundant number, since it is smaller than the sum of its proper divisors (46959520824).

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

18128240640 is an frugal number, since it uses more digits than its factorization.

18128240640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 732 (or 693 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 36.

The spelling of 18128240640 in words is "eighteen billion, one hundred twenty-eight million, two hundred forty thousand, six hundred forty".