1389528247 has 4 divisors (see below), whose sum is σ = 1396803456. Its totient is φ = 1382253040.

The previous prime is 1389528199. The next prime is 1389528263. The reversal of 1389528247 is 7428259831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7428259831 = 59 ⋅125902709.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1389528247 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1389528247.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1389528347) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3637318 + ... + 3637699.

It is an arithmetic number, because the mean of its divisors is an integer number (349200864).

Almost surely, 2^1389528247 is an apocalyptic number.

1389528247 is a deficient number, since it is larger than the sum of its proper divisors (7275209).

1389528247 is an equidigital number, since it uses as much as digits as its factorization.

1389528247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7275208.

The product of its digits is 967680, while the sum is 49.

The square root of 1389528247 is about 37276.3765272324. The cubic root of 1389528247 is about 1115.8927601612.

The spelling of 1389528247 in words is "one billion, three hundred eighty-nine million, five hundred twenty-eight thousand, two hundred forty-seven".