1221210 has 32 divisors (see below), whose sum is σ = 3257280. Its totient is φ = 325584.

The previous prime is 1221197. The next prime is 1221221. The reversal of 1221210 is 121221.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 1221192 and 1221201.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1992 + ... + 2531.

It is an arithmetic number, because the mean of its divisors is an integer number (101790).

2^1221210 is an apocalyptic number.

1221210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221210 is an abundant number, since it is smaller than the sum of its proper divisors (2036070).

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

1221210 is a wasteful number, since it uses less digits than its factorization.

1221210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4539 (or 4533 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 1221210 is about 1105.0837072367. The cubic root of 1221210 is about 106.8882870523. Note that the first 3 decimals are identical.

Adding to 1221210 its reverse (121221), we get a palindrome (1342431).

It can be divided in two parts, 1221 and 210, that added together give a triangular number (1431 = T₅₃).

The spelling of 1221210 in words is "one million, two hundred twenty-one thousand, two hundred ten".