1398289780 has 48 divisors (see below), whose sum is σ = 3114674640. Its totient is φ = 525477888.

The previous prime is 1398289771. The next prime is 1398289817. The reversal of 1398289780 is 879828931.

It can be written as a sum of positive squares in 8 ways, for example, as 57851236 + 1340438544 = 7606^2 + 36612^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 205066 + ... + 211774.

It is an arithmetic number, because the mean of its divisors is an integer number (64889055).

Almost surely, 2^1398289780 is an apocalyptic number.

1398289780 is a gapful number since it is divisible by the number (10) 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 1398289780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1557337320).

1398289780 is an abundant number, since it is smaller than the sum of its proper divisors (1716384860).

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

1398289780 is a wasteful number, since it uses less digits than its factorization.

1398289780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7348 (or 7346 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 55.

The square root of 1398289780 is about 37393.7131079544. The cubic root of 1398289780 is about 1118.2332316578.

The spelling of 1398289780 in words is "one billion, three hundred ninety-eight million, two hundred eighty-nine thousand, seven hundred eighty".