1211923 has 2 divisors, whose sum is σ = 1211924. Its totient is φ = 1211922.

The previous prime is 1211921. The next prime is 1211933. The reversal of 1211923 is 3291121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1211923 - 2¹ = 1211921 is a prime.

Together with 1211921, it forms a pair of twin primes.

1211923 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1211923.

It is not a weakly prime, because it can be changed into another prime (1211921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605961 + 605962.

It is an arithmetic number, because the mean of its divisors is an integer number (605962).

2^1211923 is an apocalyptic number.

1211923 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211923 is an equidigital number, since it uses as much as digits as its factorization.

1211923 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108, while the sum is 19.

The square root of 1211923 is about 1100.8737438962. The cubic root of 1211923 is about 106.6166442969.

It can be divided in two parts, 12 and 11923, that added together give a triangular number (11935 = T₁₅₄).

The spelling of 1211923 in words is "one million, two hundred eleven thousand, nine hundred twenty-three".