12387780 has 36 divisors (see below), whose sum is σ = 37576812. Its totient is φ = 3303360.

The previous prime is 12387779. The next prime is 12387797. The reversal of 12387780 is 8778321.

It can be written as a sum of positive squares in 2 ways, for example, as 1258884 + 11128896 = 1122^2 + 3336^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34231 + ... + 34590.

Almost surely, 2^12387780 is an apocalyptic number.

12387780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12387780 is an abundant number, since it is smaller than the sum of its proper divisors (25189032).

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

12387780 is a wasteful number, since it uses less digits than its factorization.

12387780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68836 (or 68831 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 36.

The square root of 12387780 is about 3519.6278212334. The cubic root of 12387780 is about 231.3828474564.

The spelling of 12387780 in words is "twelve million, three hundred eighty-seven thousand, seven hundred eighty".