1205778 has 32 divisors (see below), whose sum is σ = 2903040. Its totient is φ = 326160.

The previous prime is 1205773. The next prime is 1205779. The reversal of 1205778 is 8775021.

It is a happy number.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (1205773) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43 + ... + 1553.

It is an arithmetic number, because the mean of its divisors is an integer number (90720).

2^1205778 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1205778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1451520).

1205778 is an abundant number, since it is smaller than the sum of its proper divisors (1697262).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1205778 is a wasteful number, since it uses less digits than its factorization.

1205778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1542.

The product of its (nonzero) digits is 3920, while the sum is 30.

The square root of 1205778 is about 1098.0792321140. The cubic root of 1205778 is about 106.4361406050.

The spelling of 1205778 in words is "one million, two hundred five thousand, seven hundred seventy-eight".