12455775778 has 4 divisors (see below), whose sum is σ = 18683663670. Its totient is φ = 6227887888.

The previous prime is 12455775751. The next prime is 12455775779. The reversal of 12455775778 is 87757755421.

It is a happy number.

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., 6541089129 + 5914686649 = 80877^2 + 76907^2 .

It is not an unprimeable number, because it can be changed into a prime (12455775779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3113943943 + ... + 3113943946.

Almost surely, 2^12455775778 is an apocalyptic number.

12455775778 is a deficient number, since it is larger than the sum of its proper divisors (6227887892).

12455775778 is an equidigital number, since it uses as much as digits as its factorization.

12455775778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6227887891.

The product of its digits is 19208000, while the sum is 58.

The spelling of 12455775778 in words is "twelve billion, four hundred fifty-five million, seven hundred seventy-five thousand, seven hundred seventy-eight".