1216780 has 24 divisors (see below), whose sum is σ = 2589552. Its totient is φ = 480192.

The previous prime is 1216777. The next prime is 1216793. The reversal of 1216780 is 876121.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1294 + ... + 2026.

It is an arithmetic number, because the mean of its divisors is an integer number (107898).

2^1216780 is an apocalyptic number.

1216780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1216780 is an abundant number, since it is smaller than the sum of its proper divisors (1372772).

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

1216780 is a wasteful number, since it uses less digits than its factorization.

1216780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 825 (or 823 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 25.

The square root of 1216780 is about 1103.0775131422. The cubic root of 1216780 is about 106.7588829271.

The spelling of 1216780 in words is "one million, two hundred sixteen thousand, seven hundred eighty".