18128357640 has 96 divisors (see below), whose sum is σ = 59216465880. Its totient is φ = 4809670656.

The previous prime is 18128357633. The next prime is 18128357647. The reversal of 18128357640 is 4675382181.

18128357640 is a `hidden beast` number, since 18 + 1 + 28 + 3 + 576 + 40 = 666.

It is an interprime number because it is at equal distance from previous prime (18128357633) and next prime (18128357647).

It can be written as a sum of positive squares in 4 ways, for example, as 13483389924 + 4644967716 = 116118^2 + 68154^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (18128357647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 56889 + ... + 198728.

Almost surely, 2^18128357640 is an apocalyptic number.

18128357640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18128357640 is an abundant number, since it is smaller than the sum of its proper divisors (41088108240).

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

18128357640 is a wasteful number, since it uses less digits than its factorization.

18128357640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255831 (or 255824 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 45.

The spelling of 18128357640 in words is "eighteen billion, one hundred twenty-eight million, three hundred fifty-seven thousand, six hundred forty".