1221895 has 4 divisors (see below), whose sum is σ = 1466280. Its totient is φ = 977512.

The previous prime is 1221863. The next prime is 1221907. The reversal of 1221895 is 5981221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5981221 = 29 ⋅206249.

It is a cyclic number.

It is not a de Polignac number, because 1221895 - 2⁵ = 1221863 is a prime.

1221895 is a lucky number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122185 + ... + 122194.

It is an arithmetic number, because the mean of its divisors is an integer number (366570).

2^1221895 is an apocalyptic number.

1221895 is a deficient number, since it is larger than the sum of its proper divisors (244385).

1221895 is an equidigital number, since it uses as much as digits as its factorization.

1221895 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244384.

The product of its digits is 1440, while the sum is 28.

The square root of 1221895 is about 1105.3935950601. The cubic root of 1221895 is about 106.9082685436.

It can be divided in two parts, 1221 and 895, that added together give a square (2116 = 46²).

The spelling of 1221895 in words is "one million, two hundred twenty-one thousand, eight hundred ninety-five".