1228521440 has 48 divisors (see below), whose sum is σ = 2919224448. Its totient is φ = 488557056.

The previous prime is 1228521433. The next prime is 1228521457. The reversal of 1228521440 is 441258221.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5489 + ... + 49871.

It is an arithmetic number, because the mean of its divisors is an integer number (60817176).

Almost surely, 2^1228521440 is an apocalyptic number.

1228521440 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 1228521440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1459612224).

1228521440 is an abundant number, since it is smaller than the sum of its proper divisors (1690703008).

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

1228521440 is a wasteful number, since it uses less digits than its factorization.

1228521440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44571 (or 44563 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 29.

The square root of 1228521440 is about 35050.2701844080. The cubic root of 1228521440 is about 1071.0117777116.

Adding to 1228521440 its reverse (441258221), we get a palindrome (1669779661).

The spelling of 1228521440 in words is "one billion, two hundred twenty-eight million, five hundred twenty-one thousand, four hundred forty".