1217220 has 24 divisors (see below), whose sum is σ = 3408384. Its totient is φ = 324576.

The previous prime is 1217219. The next prime is 1217233. The reversal of 1217220 is 227121.

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

It is a self number, because there is not a number n which added to its sum of digits gives 1217220.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10084 + ... + 10203.

It is an arithmetic number, because the mean of its divisors is an integer number (142016).

2^1217220 is an apocalyptic number.

1217220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1217220 is an abundant number, since it is smaller than the sum of its proper divisors (2191164).

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

1217220 is a wasteful number, since it uses less digits than its factorization.

1217220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20299 (or 20297 counting only the distinct ones).

The product of its (nonzero) digits is 56, while the sum is 15.

The square root of 1217220 is about 1103.2769371287. The cubic root of 1217220 is about 106.7717497416.

Subtracting from 1217220 its reverse (227121), we obtain a palindrome (990099).

The spelling of 1217220 in words is "one million, two hundred seventeen thousand, two hundred twenty".