1221256 has 8 divisors (see below), whose sum is σ = 2289870. Its totient is φ = 610624.

The previous prime is 1221251. The next prime is 1221289. The reversal of 1221256 is 6521221.

It can be written as a sum of positive squares in only one way, i.e., 1069156 + 152100 = 1034^2 + 390^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (1221251) by changing a digit.

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 as a sum of consecutive naturals, namely, 76321 + ... + 76336.

2^1221256 is an apocalyptic number.

It is an amenable number.

1221256 is a deficient number, since it is larger than the sum of its proper divisors (1068614).

1221256 is a wasteful number, since it uses less digits than its factorization.

1221256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152663 (or 152659 counting only the distinct ones).

The product of its digits is 240, while the sum is 19.

The square root of 1221256 is about 1105.1045199437. The cubic root of 1221256 is about 106.8896291090.

Adding to 1221256 its reverse (6521221), we get a palindrome (7742477).

It can be divided in two parts, 122 and 1256, that added together give a triangular number (1378 = T₅₂).

The spelling of 1221256 in words is "one million, two hundred twenty-one thousand, two hundred fifty-six".