18639941040 has 360 divisors, whose sum is σ = 77105377440. Its totient is φ = 4009807872.

The previous prime is 18639941039. The next prime is 18639941041. The reversal of 18639941040 is 4014993681.

18639941040 is a `hidden beast` number, since 1 + 8 + 639 + 9 + 4 + 1 + 0 + 4 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (18639941039) and next prime (18639941041).

It is a tau number, because it is divible by the number of its divisors (360).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

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 (18639941041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 584221 + ... + 615299.

It is an arithmetic number, because the mean of its divisors is an integer number (214181604).

Almost surely, 2^18639941040 is an apocalyptic number.

18639941040 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 18639941040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38552688720).

18639941040 is an abundant number, since it is smaller than the sum of its proper divisors (58465436400).

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

18639941040 is a wasteful number, since it uses less digits than its factorization.

18639941040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31129 (or 31113 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The spelling of 18639941040 in words is "eighteen billion, six hundred thirty-nine million, nine hundred forty-one thousand, forty".