1138128420 has 288 divisors, whose sum is σ = 3903943680. Its totient is φ = 245836800.

The previous prime is 1138128419. The next prime is 1138128463. The reversal of 1138128420 is 248218311.

1138128420 = T₃₄₅ + T₃₄₆ + ... + T₁₉₀₀.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2925586 + ... + 2925974.

It is an arithmetic number, because the mean of its divisors is an integer number (13555360).

Almost surely, 2^1138128420 is an apocalyptic number.

1138128420 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 1138128420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1951971840).

1138128420 is an abundant number, since it is smaller than the sum of its proper divisors (2765815260).

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

1138128420 is a wasteful number, since it uses less digits than its factorization.

1138128420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 467 (or 454 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 30.

The square root of 1138128420 is about 33736.1589396303. The cubic root of 1138128420 is about 1044.0719368819.

The spelling of 1138128420 in words is "one billion, one hundred thirty-eight million, one hundred twenty-eight thousand, four hundred twenty".