18521819745975 has 192 divisors, whose sum is σ = 41913797345280. Its totient is φ = 7808980608000.

The previous prime is 18521819745973. The next prime is 18521819745991. The reversal of 18521819745975 is 57954791812581.

18521819745975 is a `hidden beast` number, since 1 + 8 + 5 + 2 + 1 + 81 + 97 + 459 + 7 + 5 = 666.

It is not a de Polignac number, because 18521819745975 - 2¹ = 18521819745973 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18521819745973) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 70569187 + ... + 70831163.

It is an arithmetic number, because the mean of its divisors is an integer number (218301027840).

Almost surely, 2^{18521819745975} is an apocalyptic number.

18521819745975 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

18521819745975 is an abundant number, since it is smaller than the sum of its proper divisors (23391977599305).

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

18521819745975 is a wasteful number, since it uses less digits than its factorization.

18521819745975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263167 (or 263156 counting only the distinct ones).

The product of its digits is 254016000, while the sum is 72.

The spelling of 18521819745975 in words is "eighteen trillion, five hundred twenty-one billion, eight hundred nineteen million, seven hundred forty-five thousand, nine hundred seventy-five".