1221010109 has 16 divisors (see below), whose sum is σ = 1347770880. Its totient is φ = 1096920000.

The previous prime is 1221010103. The next prime is 1221010111. The reversal of 1221010109 is 9010101221.

It is not a de Polignac number, because 1221010109 - 2¹² = 1221006013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221010103) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1100447 + ... + 1101555.

It is an arithmetic number, because the mean of its divisors is an integer number (84235680).

Almost surely, 2^1221010109 is an apocalyptic number.

It is an amenable number.

1221010109 is a deficient number, since it is larger than the sum of its proper divisors (126760771).

1221010109 is a wasteful number, since it uses less digits than its factorization.

1221010109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2212.

The product of its (nonzero) digits is 36, while the sum is 17.

The square root of 1221010109 is about 34942.9550696560. The cubic root of 1221010109 is about 1068.8245481144.

The spelling of 1221010109 in words is "one billion, two hundred twenty-one million, ten thousand, one hundred nine".