18228691393 has 16 divisors (see below), whose sum is σ = 20730604032. Its totient is φ = 15878160000.

The previous prime is 18228691387. The next prime is 18228691399. The reversal of 18228691393 is 39319682281.

It is an interprime number because it is at equal distance from previous prime (18228691387) and next prime (18228691399).

It is a cyclic number.

It is not a de Polignac number, because 18228691393 - 2¹⁷ = 18228560321 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18228691393.

It is not an unprimeable number, because it can be changed into a prime (18228691399) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 230196 + ... + 299077.

It is an arithmetic number, because the mean of its divisors is an integer number (1295662752).

Almost surely, 2^18228691393 is an apocalyptic number.

It is an amenable number.

18228691393 is a deficient number, since it is larger than the sum of its proper divisors (2501912639).

18228691393 is a wasteful number, since it uses less digits than its factorization.

18228691393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 529416.

The product of its digits is 1119744, while the sum is 52.

The spelling of 18228691393 in words is "eighteen billion, two hundred twenty-eight million, six hundred ninety-one thousand, three hundred ninety-three".