1398345728 has 52 divisors (see below), whose sum is σ = 3011568588. Its totient is φ = 645365760.

The previous prime is 1398345719. The next prime is 1398345749. The reversal of 1398345728 is 8275438931.

It can be written as a sum of positive squares in 2 ways, for example, as 76877824 + 1321467904 = 8768^2 + 36352^2 .

It is a tau number, because it is divible by the number of its divisors (52).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40118 + ... + 66378.

Almost surely, 2^1398345728 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 1398345728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1505784294).

1398345728 is an abundant number, since it is smaller than the sum of its proper divisors (1613222860).

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

1398345728 is an equidigital number, since it uses as much as digits as its factorization.

1398345728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26298 (or 26276 counting only the distinct ones).

The product of its digits is 1451520, while the sum is 50.

The square root of 1398345728 is about 37394.4611941394. The cubic root of 1398345728 is about 1118.2481456094.

The spelling of 1398345728 in words is "one billion, three hundred ninety-eight million, three hundred forty-five thousand, seven hundred twenty-eight".