12457978 has 8 divisors (see below), whose sum is σ = 20124468. Its totient is φ = 5749824.

The previous prime is 12457967. The next prime is 12457979. The reversal of 12457978 is 87975421.

It can be written as a sum of positive squares in 2 ways, for example, as 12089529 + 368449 = 3477^2 + 607^2 .

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 (12457979) 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, 239551 + ... + 239602.

Almost surely, 2^12457978 is an apocalyptic number.

12457978 is a deficient number, since it is larger than the sum of its proper divisors (7666490).

12457978 is a wasteful number, since it uses less digits than its factorization.

12457978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 479168.

The product of its digits is 141120, while the sum is 43.

The square root of 12457978 is about 3529.5860947142. The cubic root of 12457978 is about 231.8190845817.

The spelling of 12457978 in words is "twelve million, four hundred fifty-seven thousand, nine hundred seventy-eight".