1028773440 has 448 divisors, whose sum is σ = 3932651520. Its totient is φ = 252426240.

The previous prime is 1028773439. The next prime is 1028773441. The reversal of 1028773440 is 443778201.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1028773439) and next prime (1028773441).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1028773395 and 1028773404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1028773441) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 6160237 + ... + 6160403.

It is an arithmetic number, because the mean of its divisors is an integer number (8778240).

Almost surely, 2^1028773440 is an apocalyptic number.

1028773440 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 1028773440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1966325760).

1028773440 is an abundant number, since it is smaller than the sum of its proper divisors (2903878080).

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

1028773440 is a wasteful number, since it uses less digits than its factorization.

1028773440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247 (or 231 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 36.

The square root of 1028773440 is about 32074.4982813449. The cubic root of 1028773440 is about 1009.5005994313.

The spelling of 1028773440 in words is "one billion, twenty-eight million, seven hundred seventy-three thousand, four hundred forty".