1221011012 has 48 divisors (see below), whose sum is σ = 2457369600. Its totient is φ = 526538880.

The previous prime is 1221010997. The next prime is 1221011021. The reversal of 1221011012 is 2101101221.

It is a junction number, because it is equal to n+sod(n) for n = 1221010984 and 1221011002.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33689 + ... + 59807.

It is an arithmetic number, because the mean of its divisors is an integer number (51195200).

Almost surely, 2^1221011012 is an apocalyptic number.

It is an amenable number.

1221011012 is an abundant number, since it is smaller than the sum of its proper divisors (1236358588).

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

1221011012 is a wasteful number, since it uses less digits than its factorization.

1221011012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26196 (or 26194 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 1221011012 is about 34942.9679907131. The cubic root of 1221011012 is about 1068.8248115979.

Adding to 1221011012 its reverse (2101101221), we get a palindrome (3322112233).

The spelling of 1221011012 in words is "one billion, two hundred twenty-one million, eleven thousand, twelve".