12506778 has 16 divisors (see below), whose sum is σ = 27792960. Its totient is φ = 4168908.

The previous prime is 12506771. The next prime is 12506783. The reversal of 12506778 is 87760521.

It is not an unprimeable number, because it can be changed into a prime (12506771) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 115750 + ... + 115857.

It is an arithmetic number, because the mean of its divisors is an integer number (1737060).

Almost surely, 2^12506778 is an apocalyptic number.

12506778 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

12506778 is an abundant number, since it is smaller than the sum of its proper divisors (15286182).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12506778 is a wasteful number, since it uses less digits than its factorization.

12506778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231618 (or 231612 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 36.

The square root of 12506778 is about 3536.4923299790. The cubic root of 12506778 is about 232.1213816865.

The spelling of 12506778 in words is "twelve million, five hundred six thousand, seven hundred seventy-eight".