18265557648 has 80 divisors (see below), whose sum is σ = 50884687616. Its totient is φ = 5612544000.

The previous prime is 18265557637. The next prime is 18265557649. The reversal of 18265557648 is 84675556281.

It is a super-2 number, since 2×18265557648² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18265557649) 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, 449136 + ... + 488112.

Almost surely, 2^18265557648 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18265557648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25442343808).

18265557648 is an abundant number, since it is smaller than the sum of its proper divisors (32619129968).

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

18265557648 is a wasteful number, since it uses less digits than its factorization.

18265557648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39752 (or 39746 counting only the distinct ones).

The product of its digits is 16128000, while the sum is 57.

The spelling of 18265557648 in words is "eighteen billion, two hundred sixty-five million, five hundred fifty-seven thousand, six hundred forty-eight".