1221201220210 has 16 divisors (see below), whose sum is σ = 2198263481856. Its totient is φ = 488457980208.

The previous prime is 1221201220207. The next prime is 1221201220223. The reversal of 1221201220210 is 120221021221.

It is a happy number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 2584722 + ... + 3020461.

It is an arithmetic number, because the mean of its divisors is an integer number (137391467616).

Almost surely, 2^{1221201220210} is an apocalyptic number.

1221201220210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221201220210 is a deficient number, since it is larger than the sum of its proper divisors (977062261646).

1221201220210 is a wasteful number, since it uses less digits than its factorization.

1221201220210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5626977.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 1221201220210 its reverse (120221021221), we get a palindrome (1341422241431).

The spelling of 1221201220210 in words is "one trillion, two hundred twenty-one billion, two hundred one million, two hundred twenty thousand, two hundred ten".