18440475236 has 6 divisors (see below), whose sum is σ = 32270831670. Its totient is φ = 9220237616.

The previous prime is 18440475217. The next prime is 18440475241. The reversal of 18440475236 is 63257404481.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 16398339136 + 2042136100 = 128056^2 + 45190^2 .

It is a super-2 number, since 2×18440475236² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2305059401 + ... + 2305059408.

It is an arithmetic number, because the mean of its divisors is an integer number (5378471945).

Almost surely, 2^18440475236 is an apocalyptic number.

It is an amenable number.

18440475236 is a deficient number, since it is larger than the sum of its proper divisors (13830356434).

18440475236 is a wasteful number, since it uses less digits than its factorization.

18440475236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4610118813 (or 4610118811 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 44.

The spelling of 18440475236 in words is "eighteen billion, four hundred forty million, four hundred seventy-five thousand, two hundred thirty-six".