18747359281 has 12 divisors (see below), whose sum is σ = 21814526772. Its totient is φ = 16064468448.

The previous prime is 18747359269. The next prime is 18747359287. The reversal of 18747359281 is 18295374781.

It can be written as a sum of positive squares in 2 ways, for example, as 6077605681 + 12669753600 = 77959^2 + 112560^2 .

It is not a de Polignac number, because 18747359281 - 2⁵ = 18747359249 is a prime.

It is a super-2 number, since 2×18747359281² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18747359287) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 118971 + ... + 227263.

It is an arithmetic number, because the mean of its divisors is an integer number (1817877231).

Almost surely, 2^18747359281 is an apocalyptic number.

It is an amenable number.

18747359281 is a deficient number, since it is larger than the sum of its proper divisors (3067167491).

18747359281 is a wasteful number, since it uses less digits than its factorization.

18747359281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111840 (or 111833 counting only the distinct ones).

The product of its digits is 3386880, while the sum is 55.

The spelling of 18747359281 in words is "eighteen billion, seven hundred forty-seven million, three hundred fifty-nine thousand, two hundred eighty-one".