1211755 has 16 divisors (see below), whose sum is σ = 1560384. Its totient is φ = 901120.

The previous prime is 1211741. The next prime is 1211761. The reversal of 1211755 is 5571121.

It is not a de Polignac number, because 1211755 - 2⁵ = 1211723 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 4587 + ... + 4843.

It is an arithmetic number, because the mean of its divisors is an integer number (97524).

2^1211755 is an apocalyptic number.

1211755 is a deficient number, since it is larger than the sum of its proper divisors (348629).

1211755 is a wasteful number, since it uses less digits than its factorization.

1211755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 326.

The product of its digits is 350, while the sum is 22.

The square root of 1211755 is about 1100.7974382238. The cubic root of 1211755 is about 106.6117175747.

Adding to 1211755 its reverse (5571121), we get a palindrome (6782876).

It can be divided in two parts, 12117 and 55, that multiplied together give a triangular number (666435 = T₁₁₅₄).

The spelling of 1211755 in words is "one million, two hundred eleven thousand, seven hundred fifty-five".