1255681 has 4 divisors (see below), whose sum is σ = 1435072. Its totient is φ = 1076292.

The previous prime is 1255679. The next prime is 1255687. The reversal of 1255681 is 1865521.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1255681 - 2¹ = 1255679 is a prime.

It is a super-2 number, since 2×1255681² = 3153469547522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1255687) 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 in 3 ways as a sum of consecutive naturals, for example, 89685 + ... + 89698.

It is an arithmetic number, because the mean of its divisors is an integer number (358768).

2^1255681 is an apocalyptic number.

It is an amenable number.

1255681 is a deficient number, since it is larger than the sum of its proper divisors (179391).

1255681 is an equidigital number, since it uses as much as digits as its factorization.

1255681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179390.

The product of its digits is 2400, while the sum is 28.

The square root of 1255681 is about 1120.5717290740. The cubic root of 1255681 is about 107.8846791464.

It can be divided in two parts, 1255 and 681, that added together give a square (1936 = 44²).

The spelling of 1255681 in words is "one million, two hundred fifty-five thousand, six hundred eighty-one".