18281594640 has 80 divisors (see below), whose sum is σ = 60006659328. Its totient is φ = 4588320768.

The previous prime is 18281594633. The next prime is 18281594641. The reversal of 18281594640 is 4649518281.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 18281594640.

It is not an unprimeable number, because it can be changed into a prime (18281594641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2236312 + ... + 2244471.

Almost surely, 2^18281594640 is an apocalyptic number.

18281594640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18281594640 is an abundant number, since it is smaller than the sum of its proper divisors (41725064688).

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

18281594640 is a wasteful number, since it uses less digits than its factorization.

18281594640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4480816 (or 4480810 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 48.

The spelling of 18281594640 in words is "eighteen billion, two hundred eighty-one million, five hundred ninety-four thousand, six hundred forty".