12739978 has 8 divisors (see below), whose sum is σ = 19178820. Its totient is φ = 6347040.

The previous prime is 12739973. The next prime is 12740003. The reversal of 12739978 is 87993721.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 10843849 + 1896129 = 3293^2 + 1377^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (12739973) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10773 + ... + 11896.

Almost surely, 2^12739978 is an apocalyptic number.

12739978 is a deficient number, since it is larger than the sum of its proper divisors (6438842).

12739978 is a wasteful number, since it uses less digits than its factorization.

12739978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22952.

The product of its digits is 190512, while the sum is 46.

The square root of 12739978 is about 3569.3105776886. The cubic root of 12739978 is about 233.5552098126. Note that the first 3 decimals are identical.

The spelling of 12739978 in words is "twelve million, seven hundred thirty-nine thousand, nine hundred seventy-eight".