1398856640 has 56 divisors (see below), whose sum is σ = 3339297360. Its totient is φ = 558153728.

The previous prime is 1398856633. The next prime is 1398856651. The reversal of 1398856640 is 466588931.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 128864 + ... + 139296.

It is an arithmetic number, because the mean of its divisors is an integer number (59630310).

Almost surely, 2^1398856640 is an apocalyptic number.

1398856640 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 1398856640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1669648680).

1398856640 is an abundant number, since it is smaller than the sum of its proper divisors (1940440720).

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

1398856640 is a wasteful number, since it uses less digits than its factorization.

1398856640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10869 (or 10859 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 50.

The square root of 1398856640 is about 37401.2919562948. The cubic root of 1398856640 is about 1118.3843200469.

The spelling of 1398856640 in words is "one billion, three hundred ninety-eight million, eight hundred fifty-six thousand, six hundred forty".