1389540528 has 320 divisors, whose sum is σ = 4469555200. Its totient is φ = 411505920.

The previous prime is 1389540521. The next prime is 1389540541. The reversal of 1389540528 is 8250459831.

1389540528 is a `hidden beast` number, since 1 + 3 + 89 + 5 + 40 + 528 = 666.

It is not an unprimeable number, because it can be changed into a prime (1389540521) 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, 10941201 + ... + 10941327.

It is an arithmetic number, because the mean of its divisors is an integer number (13967360).

Almost surely, 2^1389540528 is an apocalyptic number.

1389540528 is a gapful number since it is divisible by the number (18) 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 1389540528, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2234777600).

1389540528 is an abundant number, since it is smaller than the sum of its proper divisors (3080014672).

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

1389540528 is a wasteful number, since it uses less digits than its factorization.

1389540528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237 (or 225 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 45.

The square root of 1389540528 is about 37276.5412558622. The cubic root of 1389540528 is about 1115.8960476651.

The spelling of 1389540528 in words is "one billion, three hundred eighty-nine million, five hundred forty thousand, five hundred twenty-eight".