18946721153 has 16 divisors (see below), whose sum is σ = 20414592000. Its totient is φ = 17518509312.

The previous prime is 18946721141. The next prime is 18946721179. The reversal of 18946721153 is 35112764981.

It is a cyclic number.

It is not a de Polignac number, because 18946721153 - 2¹⁴ = 18946704769 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18946721098 and 18946721107.

It is not an unprimeable number, because it can be changed into a prime (18946721113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1789088 + ... + 1799646.

It is an arithmetic number, because the mean of its divisors is an integer number (1275912000).

Almost surely, 2^18946721153 is an apocalyptic number.

It is an amenable number.

18946721153 is a deficient number, since it is larger than the sum of its proper divisors (1467870847).

18946721153 is a wasteful number, since it uses less digits than its factorization.

18946721153 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12424.

The product of its digits is 362880, while the sum is 47.

The spelling of 18946721153 in words is "eighteen billion, nine hundred forty-six million, seven hundred twenty-one thousand, one hundred fifty-three".