18178342640 has 20 divisors (see below), whose sum is σ = 42264646824. Its totient is φ = 7271337024.

The previous prime is 18178342639. The next prime is 18178342643. The reversal of 18178342640 is 4624387181.

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×18178342640² (a number of 21 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (44) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 18178342591 and 18178342600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18178342643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113614562 + ... + 113614721.

Almost surely, 2^18178342640 is an apocalyptic number.

18178342640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18178342640 is an abundant number, since it is smaller than the sum of its proper divisors (24086304184).

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

18178342640 is a wasteful number, since it uses less digits than its factorization.

18178342640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227229296 (or 227229290 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 44.

The spelling of 18178342640 in words is "eighteen billion, one hundred seventy-eight million, three hundred forty-two thousand, six hundred forty".