12943137778 has 4 divisors (see below), whose sum is σ = 19414706670. Its totient is φ = 6471568888.

The previous prime is 12943137751. The next prime is 12943137797. The reversal of 12943137778 is 87773134921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87773134921 = 87869 ⋅998909.

It can be written as a sum of positive squares in only one way, i.e., 10596025969 + 2347111809 = 102937^2 + 48447^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3235784443 + ... + 3235784446.

Almost surely, 2^12943137778 is an apocalyptic number.

12943137778 is a deficient number, since it is larger than the sum of its proper divisors (6471568892).

12943137778 is an equidigital number, since it uses as much as digits as its factorization.

12943137778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6471568891.

The product of its digits is 1778112, while the sum is 52.

The spelling of 12943137778 in words is "twelve billion, nine hundred forty-three million, one hundred thirty-seven thousand, seven hundred seventy-eight".