1221210112 has 52 divisors (see below), whose sum is σ = 2451533536. Its totient is φ = 608256000.

The previous prime is 1221210043. The next prime is 1221210119. The reversal of 1221210112 is 2110121221.

It is a junction number, because it is equal to n+sod(n) for n = 1221210092 and 1221210101.

It is not an unprimeable number, because it can be changed into a prime (1221210119) 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, 1625737 + ... + 1626487.

Almost surely, 2^1221210112 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221210112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1225766768).

1221210112 is an abundant number, since it is smaller than the sum of its proper divisors (1230323424).

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

1221210112 is an frugal number, since it uses more digits than its factorization.

1221210112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1172 (or 1150 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 1221210112 is about 34945.8168025874. The cubic root of 1221210112 is about 1068.8829031992.

Adding to 1221210112 its reverse (2110121221), we get a palindrome (3331331333).

The spelling of 1221210112 in words is "one billion, two hundred twenty-one million, two hundred ten thousand, one hundred twelve".