1389801644 has 72 divisors (see below), whose sum is σ = 3087493920. Its totient is φ = 535772160.

The previous prime is 1389801619. The next prime is 1389801653. The reversal of 1389801644 is 4461089831.

It is a hoax number, since the sum of its digits (44) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 1389801595 and 1389801604.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 326522 + ... + 330750.

It is an arithmetic number, because the mean of its divisors is an integer number (42881860).

Almost surely, 2^1389801644 is an apocalyptic number.

1389801644 is a gapful number since it is divisible by the number (14) 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 1389801644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1543746960).

1389801644 is an abundant number, since it is smaller than the sum of its proper divisors (1697692276).

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

1389801644 is a wasteful number, since it uses less digits than its factorization.

1389801644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4359 (or 4346 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 44.

The square root of 1389801644 is about 37280.0435085583. The cubic root of 1389801644 is about 1115.9659412875.

The spelling of 1389801644 in words is "one billion, three hundred eighty-nine million, eight hundred one thousand, six hundred forty-four".