1221012210 has 96 divisors (see below), whose sum is σ = 3308469696. Its totient is φ = 287971200.

The previous prime is 1221012209. The next prime is 1221012227. The reversal of 1221012210 is 122101221.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 129765 + ... + 138855.

It is an arithmetic number, because the mean of its divisors is an integer number (34463226).

Almost surely, 2^1221012210 is an apocalyptic number.

1221012210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221012210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1654234848).

1221012210 is an abundant number, since it is smaller than the sum of its proper divisors (2087457486).

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

1221012210 is a wasteful number, since it uses less digits than its factorization.

1221012210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9160 (or 9149 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 1221012210 is about 34942.9851329276. The cubic root of 1221012210 is about 1068.8251611585.

Adding to 1221012210 its reverse (122101221), we get a palindrome (1343113431).

The spelling of 1221012210 in words is "one billion, two hundred twenty-one million, twelve thousand, two hundred ten".