18083473778 has 4 divisors (see below), whose sum is σ = 27125210670. Its totient is φ = 9041736888.

The previous prime is 18083473777. The next prime is 18083473789. The reversal of 18083473778 is 87737438081.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 18035684209 + 47789569 = 134297^2 + 6913^2 .

It is a super-2 number, since 2×18083473778² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18083473777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4520868443 + ... + 4520868446.

Almost surely, 2^18083473778 is an apocalyptic number.

18083473778 is a deficient number, since it is larger than the sum of its proper divisors (9041736892).

18083473778 is an equidigital number, since it uses as much as digits as its factorization.

18083473778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9041736891.

The product of its (nonzero) digits is 6322176, while the sum is 56.

The spelling of 18083473778 in words is "eighteen billion, eighty-three million, four hundred seventy-three thousand, seven hundred seventy-eight".