1321231212 has 36 divisors (see below), whose sum is σ = 3816890896. Its totient is φ = 377494560.

The previous prime is 1321231207. The next prime is 1321231217. The reversal of 1321231212 is 2121321231.

It is an interprime number because it is at equal distance from previous prime (1321231207) and next prime (1321231217).

It is a tau number, because it is divible by the number of its divisors (36).

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 not an unprimeable number, because it can be changed into a prime (1321231217) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2621239 + ... + 2621742.

Almost surely, 2^1321231212 is an apocalyptic number.

1321231212 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1321231212 is an abundant number, since it is smaller than the sum of its proper divisors (2495659684).

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

1321231212 is a wasteful number, since it uses less digits than its factorization.

1321231212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5242998 (or 5242993 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 1321231212 is about 36348.7442974307. The cubic root of 1321231212 is about 1097.3022630701.

Adding to 1321231212 its reverse (2121321231), we get a palindrome (3442552443).

The spelling of 1321231212 in words is "one billion, three hundred twenty-one million, two hundred thirty-one thousand, two hundred twelve".