1226821440 has 224 divisors, whose sum is σ = 4224528000. Its totient is φ = 299851776.

The previous prime is 1226821417. The next prime is 1226821441. The reversal of 1226821440 is 441286221.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 1226821398 and 1226821407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1226821441) 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, 2458311 + ... + 2458809.

It is an arithmetic number, because the mean of its divisors is an integer number (18859500).

Almost surely, 2^1226821440 is an apocalyptic number.

1226821440 is a gapful number since it is divisible by the number (10) 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 1226821440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2112264000).

1226821440 is an abundant number, since it is smaller than the sum of its proper divisors (2997706560).

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

1226821440 is a wasteful number, since it uses less digits than its factorization.

1226821440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 729 (or 719 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 30.

The square root of 1226821440 is about 35026.0109061823. The cubic root of 1226821440 is about 1070.5175357628.

The spelling of 1226821440 in words is "one billion, two hundred twenty-six million, eight hundred twenty-one thousand, four hundred forty".