1389661056 has 512 divisors, whose sum is σ = 5170176000. Its totient is φ = 358318080.

The previous prime is 1389661037. The next prime is 1389661067. The reversal of 1389661056 is 6501669831.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 12749130 + ... + 12749238.

It is an arithmetic number, because the mean of its divisors is an integer number (10098000).

Almost surely, 2^1389661056 is an apocalyptic number.

1389661056 is a gapful number since it is divisible by the number (16) 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 1389661056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2585088000).

1389661056 is an abundant number, since it is smaller than the sum of its proper divisors (3780514944).

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

1389661056 is a wasteful number, since it uses less digits than its factorization.

1389661056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187 (or 169 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 45.

The square root of 1389661056 is about 37278.1578944025. The cubic root of 1389661056 is about 1115.9283108071.

The spelling of 1389661056 in words is "one billion, three hundred eighty-nine million, six hundred sixty-one thousand, fifty-six".