12501778 has 4 divisors (see below), whose sum is σ = 18752670. Its totient is φ = 6250888.

The previous prime is 12501739. The next prime is 12501779. The reversal of 12501778 is 87710521.

It is a happy number.

12501778 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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., 7823209 + 4678569 = 2797^2 + 2163^2 .

It is a super-2 number, since 2×12501778² = 312588906322568, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (12501779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3125443 + ... + 3125446.

Almost surely, 2^12501778 is an apocalyptic number.

12501778 is a deficient number, since it is larger than the sum of its proper divisors (6250892).

12501778 is an equidigital number, since it uses as much as digits as its factorization.

12501778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6250891.

The product of its (nonzero) digits is 3920, while the sum is 31.

The square root of 12501778 is about 3535.7853441633. The cubic root of 12501778 is about 232.0904448189.

The spelling of 12501778 in words is "twelve million, five hundred one thousand, seven hundred seventy-eight".