1221000210 has 32 divisors (see below), whose sum is σ = 3256001280. Its totient is φ = 325599984.

The previous prime is 1221000203. The next prime is 1221000227. The reversal of 1221000210 is 120001221.

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 = 1221000192 and 1221000201.

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, 2260842 + ... + 2261381.

It is an arithmetic number, because the mean of its divisors is an integer number (101750040).

Almost surely, 2^1221000210 is an apocalyptic number.

1221000210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221000210 is an abundant number, since it is smaller than the sum of its proper divisors (2035001070).

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

1221000210 is a wasteful number, since it uses less digits than its factorization.

1221000210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4522239 (or 4522233 counting only the distinct ones).

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

The square root of 1221000210 is about 34942.8134242222. The cubic root of 1221000210 is about 1068.8216597073.

Adding to 1221000210 its reverse (120001221), we get a palindrome (1341001431).

The spelling of 1221000210 in words is "one billion, two hundred twenty-one million, two hundred ten", and thus it is an aban number.