7728745444 has 96 divisors (see below), whose sum is σ = 16767959040. Its totient is φ = 3042748800.

The previous prime is 7728745441. The next prime is 7728745447. The reversal of 7728745444 is 4445478277.

It is an interprime number because it is at equal distance from previous prime (7728745441) and next prime (7728745447).

It is a super-2 number, since 2×7728745444² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 7728745391 and 7728745400.

It is not an unprimeable number, because it can be changed into a prime (7728745441) 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, 8483349 + ... + 8484259.

It is an arithmetic number, because the mean of its divisors is an integer number (174666240).

Almost surely, 2^7728745444 is an apocalyptic number.

7728745444 is a gapful number since it is divisible by the number (74) 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 7728745444, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8383979520).

7728745444 is an abundant number, since it is smaller than the sum of its proper divisors (9039213596).

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

7728745444 is a wasteful number, since it uses less digits than its factorization.

7728745444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1409 (or 1407 counting only the distinct ones).

The product of its digits is 7024640, while the sum is 52.

The square root of 7728745444 is about 87913.2836606619. The cubic root of 7728745444 is about 1977.1350467853.

The spelling of 7728745444 in words is "seven billion, seven hundred twenty-eight million, seven hundred forty-five thousand, four hundred forty-four".