18426320640 has 1512 divisors, whose sum is σ = 85574659968. Its totient is φ = 3762339840.

The previous prime is 18426320603. The next prime is 18426320657. The reversal of 18426320640 is 4602362481.

18426320640 is a `hidden beast` number, since 1 + 8 + 4 + 2 + 6 + 3 + 2 + 0 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (1512).

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 = 18426320595 and 18426320604.

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 167 ways as a sum of consecutive naturals, for example, 594397425 + ... + 594397455.

Almost surely, 2^18426320640 is an apocalyptic number.

18426320640 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 18426320640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42787329984).

18426320640 is an abundant number, since it is smaller than the sum of its proper divisors (67148339328).

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

18426320640 is an equidigital number, since it uses as much as digits as its factorization.

18426320640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97 (or 61 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The spelling of 18426320640 in words is "eighteen billion, four hundred twenty-six million, three hundred twenty thousand, six hundred forty".