1221220210 has 64 divisors (see below), whose sum is σ = 2579334912. Its totient is φ = 407586816.

The previous prime is 1221220199. The next prime is 1221220229. The reversal of 1221220210 is 120221221.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1302862 + ... + 1303798.

It is an arithmetic number, because the mean of its divisors is an integer number (40302108).

Almost surely, 2^1221220210 is an apocalyptic number.

1221220210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221220210 is an abundant number, since it is smaller than the sum of its proper divisors (1358114702).

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

1221220210 is a wasteful number, since it uses less digits than its factorization.

1221220210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1427.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 1221220210 is about 34945.9612831011. The cubic root of 1221220210 is about 1068.8858493342.

Adding to 1221220210 its reverse (120221221), we get a palindrome (1341441431).

The spelling of 1221220210 in words is "one billion, two hundred twenty-one million, two hundred twenty thousand, two hundred ten".