18013480821549 has 24 divisors (see below), whose sum is σ = 26523682255512. Its totient is φ = 11776501875840.

The previous prime is 18013480821473. The next prime is 18013480821587. The reversal of 18013480821549 is 94512808431081.

18013480821549 is a `hidden beast` number, since 1 + 8 + 0 + 1 + 3 + 480 + 8 + 2 + 154 + 9 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 328243055625 + 17685237765924 = 572925^2 + 4205382^2 .

It is not a de Polignac number, because 18013480821549 - 2⁷ = 18013480821421 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18013480821495 and 18013480821504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18013480821599) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8502642 + ... + 10407779.

It is an arithmetic number, because the mean of its divisors is an integer number (1105153427313).

Almost surely, 2^{18013480821549} is an apocalyptic number.

It is an amenable number.

18013480821549 is a deficient number, since it is larger than the sum of its proper divisors (8510201433963).

18013480821549 is a wasteful number, since it uses less digits than its factorization.

18013480821549 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18912477 (or 18912474 counting only the distinct ones).

The product of its (nonzero) digits is 2211840, while the sum is 54.

The spelling of 18013480821549 in words is "eighteen trillion, thirteen billion, four hundred eighty million, eight hundred twenty-one thousand, five hundred forty-nine".