1438405128 has 80 divisors (see below), whose sum is σ = 4044226560. Its totient is φ = 477640800.

The previous prime is 1438405121. The next prime is 1438405183. The reversal of 1438405128 is 8215048341.

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 = 1438405092 and 1438405101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1438405121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 171513 + ... + 179703.

It is an arithmetic number, because the mean of its divisors is an integer number (50552832).

Almost surely, 2^1438405128 is an apocalyptic number.

1438405128 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 1438405128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2022113280).

1438405128 is an abundant number, since it is smaller than the sum of its proper divisors (2605821432).

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

1438405128 is a wasteful number, since it uses less digits than its factorization.

1438405128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8480 (or 8467 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The square root of 1438405128 is about 37926.3118164685. The cubic root of 1438405128 is about 1128.8261828692.

The spelling of 1438405128 in words is "one billion, four hundred thirty-eight million, four hundred five thousand, one hundred twenty-eight".