1221432312 has 64 divisors (see below), whose sum is σ = 3172296960. Its totient is φ = 391596800.

The previous prime is 1221432307. The next prime is 1221432361. The reversal of 1221432312 is 2132341221.

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

It is a congruent number.

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, 61123 + ... + 78605.

It is an arithmetic number, because the mean of its divisors is an integer number (49567140).

Almost surely, 2^1221432312 is an apocalyptic number.

1221432312 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 1221432312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1586148480).

1221432312 is an abundant number, since it is smaller than the sum of its proper divisors (1950864648).

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

1221432312 is a wasteful number, since it uses less digits than its factorization.

1221432312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17604 (or 17600 counting only the distinct ones).

The product of its digits is 576, while the sum is 21.

The square root of 1221432312 is about 34948.9958654036. The cubic root of 1221432312 is about 1068.9477272551.

Adding to 1221432312 its reverse (2132341221), we get a palindrome (3353773533).

The spelling of 1221432312 in words is "one billion, two hundred twenty-one million, four hundred thirty-two thousand, three hundred twelve".