18894145537 has 4 divisors (see below), whose sum is σ = 18894423600. Its totient is φ = 18893867476.

The previous prime is 18894145531. The next prime is 18894145541. The reversal of 18894145537 is 73554149881.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18894145537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18894145531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38214 + ... + 198112.

It is an arithmetic number, because the mean of its divisors is an integer number (4723605900).

Almost surely, 2^18894145537 is an apocalyptic number.

It is an amenable number.

18894145537 is a deficient number, since it is larger than the sum of its proper divisors (278063).

18894145537 is a wasteful number, since it uses less digits than its factorization.

18894145537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278062.

The product of its digits is 4838400, while the sum is 55.

The spelling of 18894145537 in words is "eighteen billion, eight hundred ninety-four million, one hundred forty-five thousand, five hundred thirty-seven".