1276821 has 24 divisors (see below), whose sum is σ = 2271360. Its totient is φ = 673056.

The previous prime is 1276817. The next prime is 1276829. The reversal of 1276821 is 1286721.

It is not a de Polignac number, because 1276821 - 2² = 1276817 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1276829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40 + ... + 1598.

It is an arithmetic number, because the mean of its divisors is an integer number (94640).

2^1276821 is an apocalyptic number.

It is an amenable number.

1276821 is a deficient number, since it is larger than the sum of its proper divisors (994539).

1276821 is a wasteful number, since it uses less digits than its factorization.

1276821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1585 (or 1582 counting only the distinct ones).

The product of its digits is 1344, while the sum is 27.

The square root of 1276821 is about 1129.9650437071. The cubic root of 1276821 is about 108.4867433385.

The spelling of 1276821 in words is "one million, two hundred seventy-six thousand, eight hundred twenty-one".