1221321300210 has 128 divisors (see below), whose sum is σ = 3601605669120. Its totient is φ = 292021977600.

The previous prime is 1221321300209. The next prime is 1221321300217. The reversal of 1221321300210 is 120031231221.

1221321300210 is a `hidden beast` number, since 1 + 2 + 21 + 321 + 300 + 21 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (1221321300217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2599761 + ... + 3033380.

It is an arithmetic number, because the mean of its divisors is an integer number (28137544290).

Almost surely, 2^{1221321300210} is an apocalyptic number.

1221321300210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221321300210 is an abundant number, since it is smaller than the sum of its proper divisors (2380284368910).

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

1221321300210 is a wasteful number, since it uses less digits than its factorization.

1221321300210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5633241 (or 5633235 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 1221321300210 its reverse (120031231221), we get a palindrome (1341352531431).

The spelling of 1221321300210 in words is "one trillion, two hundred twenty-one billion, three hundred twenty-one million, three hundred thousand, two hundred ten".