1399120128 has 486 divisors, whose sum is σ = 5159498526. Its totient is φ = 376233984.

The previous prime is 1399120103. The next prime is 1399120181. The reversal of 1399120128 is 8210219931.

It can be written as a sum of positive squares in only one way, i.e., 1316818944 + 82301184 = 36288^2 + 9072^2 .

It is a tau number, because it is divible by the number of its divisors (486).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1399120092 and 1399120101.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 82301176 + ... + 82301192.

Almost surely, 2^1399120128 is an apocalyptic number.

1399120128 is a gapful number since it is divisible by the number (18) 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 1399120128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2579749263).

1399120128 is an abundant number, since it is smaller than the sum of its proper divisors (3760378398).

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

1399120128 is an frugal number, since it uses more digits than its factorization.

1399120128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71 (or 29 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

The square root of 1399120128 is about 37404.8142356034. The cubic root of 1399120128 is about 1118.4545350924.

The spelling of 1399120128 in words is "one billion, three hundred ninety-nine million, one hundred twenty thousand, one hundred twenty-eight".