1221322212 has 90 divisors (see below), whose sum is σ = 3509529254. Its totient is φ = 370085760.

The previous prime is 1221322127. The next prime is 1221322231. The reversal of 1221322212 is 2122231221.

1221322212 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 917726436 + 303595776 = 30294^2 + 17424^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 23628 + ... + 54780.

Almost surely, 2^1221322212 is an apocalyptic number.

1221322212 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221322212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1754764627).

1221322212 is an abundant number, since it is smaller than the sum of its proper divisors (2288207042).

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

1221322212 is a wasteful number, since it uses less digits than its factorization.

1221322212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31191 (or 31169 counting only the distinct ones).

The product of its digits is 192, while the sum is 18.

The square root of 1221322212 is about 34947.4206773547. The cubic root of 1221322212 is about 1068.9156079473.

Adding to 1221322212 its reverse (2122231221), we get a palindrome (3343553433).

Subtracting 1221322212 from its reverse (2122231221), we obtain a palindrome (900909009).

The spelling of 1221322212 in words is "one billion, two hundred twenty-one million, three hundred twenty-two thousand, two hundred twelve".