1221206210 has 16 divisors (see below), whose sum is σ = 2512195776. Its totient is φ = 418699248.

The previous prime is 1221206179. The next prime is 1221206221. The reversal of 1221206210 is 126021221.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8722832 + ... + 8722971.

It is an arithmetic number, because the mean of its divisors is an integer number (157012236).

Almost surely, 2^1221206210 is an apocalyptic number.

1221206210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221206210 is an abundant number, since it is smaller than the sum of its proper divisors (1290989566).

1221206210 is a wasteful number, since it uses less digits than its factorization.

1221206210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17445817.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 1221206210 is about 34945.7609732568. The cubic root of 1221206210 is about 1068.8817647695.

Adding to 1221206210 its reverse (126021221), we get a palindrome (1347227431).

The spelling of 1221206210 in words is "one billion, two hundred twenty-one million, two hundred six thousand, two hundred ten".