1389309408 has 60 divisors (see below), whose sum is σ = 4085928000. Its totient is φ = 463102272.

The previous prime is 1389309391. The next prime is 1389309419. The reversal of 1389309408 is 8049039831.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 265408 + ... + 270591.

It is an arithmetic number, because the mean of its divisors is an integer number (68098800).

Almost surely, 2^1389309408 is an apocalyptic number.

1389309408 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1389309408 is an abundant number, since it is smaller than the sum of its proper divisors (2696618592).

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

1389309408 is an equidigital number, since it uses as much as digits as its factorization.

1389309408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 536021 (or 536004 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 1389309408 is about 37273.4410539193. The cubic root of 1389309408 is about 1115.8341758474.

The spelling of 1389309408 in words is "one billion, three hundred eighty-nine million, three hundred nine thousand, four hundred eight".