1220505 has 32 divisors (see below), whose sum is σ = 2298240. Its totient is φ = 545280.

The previous prime is 1220497. The next prime is 1220507. The reversal of 1220505 is 5050221.

It is not a de Polignac number, because 1220505 - 2³ = 1220497 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

1220505 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220507) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1861 + ... + 2429.

It is an arithmetic number, because the mean of its divisors is an integer number (71820).

2^1220505 is an apocalyptic number.

1220505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1220505 is a deficient number, since it is larger than the sum of its proper divisors (1077735).

1220505 is a wasteful number, since it uses less digits than its factorization.

1220505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 601.

The product of its (nonzero) digits is 100, while the sum is 15.

The square root of 1220505 is about 1104.7646808257. The cubic root of 1220505 is about 106.8677143558.

Adding to 1220505 its reverse (5050221), we get a palindrome (6270726).

The spelling of 1220505 in words is "one million, two hundred twenty thousand, five hundred five".