1221203116 has 12 divisors (see below), whose sum is σ = 2442406288. Its totient is φ = 523372752.

The previous prime is 1221203089. The next prime is 1221203117. The reversal of 1221203116 is 6113021221.

1221203116 is an admirable number.

It is a super-3 number, since 3×1221203116³ (a number of 28 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1221203093 and 1221203102.

It is not an unprimeable number, because it can be changed into a prime (1221203117) 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, 21807171 + ... + 21807226.

Almost surely, 2^1221203116 is an apocalyptic number.

It is an amenable number.

1221203116 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

1221203116 is a wasteful number, since it uses less digits than its factorization.

1221203116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43614408 (or 43614406 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 1221203116 is about 34945.7167046263. The cubic root of 1221203116 is about 1068.8808620764.

Adding to 1221203116 its reverse (6113021221), we get a palindrome (7334224337).

The spelling of 1221203116 in words is "one billion, two hundred twenty-one million, two hundred three thousand, one hundred sixteen".