1221020110 has 8 divisors (see below), whose sum is σ = 2197836216. Its totient is φ = 488408040.

The previous prime is 1221020093. The next prime is 1221020111. The reversal of 1221020110 is 110201221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Harshad number since it is a multiple of its sum of digits (10), and also a Moran number because the ratio is a prime number: 122102011 = 1221020110 / (1 + 2 + 2 + 1 + 0 + 2 + 0 + 1 + 1 + 0).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221020111) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61050996 + ... + 61051015.

It is an arithmetic number, because the mean of its divisors is an integer number (274729527).

Almost surely, 2^1221020110 is an apocalyptic number.

1221020110 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221020110 is a deficient number, since it is larger than the sum of its proper divisors (976816106).

1221020110 is a wasteful number, since it uses less digits than its factorization.

1221020110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122102018.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 1221020110 is about 34943.0981740314. The cubic root of 1221020110 is about 1068.8274662680.

Adding to 1221020110 its reverse (110201221), we get a palindrome (1331221331).

The spelling of 1221020110 in words is "one billion, two hundred twenty-one million, twenty thousand, one hundred ten".