18455158638 has 128 divisors (see below), whose sum is σ = 48829440000. Its totient is φ = 5055644160.

The previous prime is 18455158621. The next prime is 18455158651. The reversal of 18455158638 is 83685155481.

18455158638 is a `hidden beast` number, since 1 + 8 + 4 + 5 + 51 + 586 + 3 + 8 = 666.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 1270038 + ... + 1284486.

It is an arithmetic number, because the mean of its divisors is an integer number (381480000).

Almost surely, 2^18455158638 is an apocalyptic number.

18455158638 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 18455158638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24414720000).

18455158638 is an abundant number, since it is smaller than the sum of its proper divisors (30374281362).

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

18455158638 is a wasteful number, since it uses less digits than its factorization.

18455158638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14607 (or 14601 counting only the distinct ones).

The product of its digits is 4608000, while the sum is 54.

The spelling of 18455158638 in words is "eighteen billion, four hundred fifty-five million, one hundred fifty-eight thousand, six hundred thirty-eight".