18321425640 has 1280 divisors, whose sum is σ = 81669772800. Its totient is φ = 3583180800.

The previous prime is 18321425627. The next prime is 18321425651. The reversal of 18321425640 is 4652412381.

It is a happy number.

18321425640 is a `hidden beast` number, since 1 + 8 + 3 + 2 + 1 + 4 + 2 + 5 + 640 = 666.

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 = 18321425595 and 18321425604.

It is an unprimeable number.

It is a polite number, since it can be written in 319 ways as a sum of consecutive naturals, for example, 300351210 + ... + 300351270.

It is an arithmetic number, because the mean of its divisors is an integer number (63804510).

Almost surely, 2^18321425640 is an apocalyptic number.

18321425640 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 18321425640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40834886400).

18321425640 is an abundant number, since it is smaller than the sum of its proper divisors (63348347160).

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

18321425640 is a wasteful number, since it uses less digits than its factorization.

18321425640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168 (or 155 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The spelling of 18321425640 in words is "eighteen billion, three hundred twenty-one million, four hundred twenty-five thousand, six hundred forty".