1221421344 has 192 divisors, whose sum is σ = 3794491008. Its totient is φ = 339148800.

The previous prime is 1221421343. The next prime is 1221421367. The reversal of 1221421344 is 4431241221.

It is a Harshad number since it is a multiple of its sum of digits (24).

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 (1221421343) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2649274 + ... + 2649734.

It is an arithmetic number, because the mean of its divisors is an integer number (19762974).

Almost surely, 2^1221421344 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 1221421344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1897245504).

1221421344 is an abundant number, since it is smaller than the sum of its proper divisors (2573069664).

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

1221421344 is a wasteful number, since it uses less digits than its factorization.

1221421344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 691 (or 683 counting only the distinct ones).

The product of its digits is 1536, while the sum is 24.

The square root of 1221421344 is about 34948.8389506719. The cubic root of 1221421344 is about 1068.9445276635.

Adding to 1221421344 its reverse (4431241221), we get a palindrome (5652662565).

The spelling of 1221421344 in words is "one billion, two hundred twenty-one million, four hundred twenty-one thousand, three hundred forty-four".