128838040840 has 64 divisors (see below), whose sum is σ = 297030751920. Its totient is φ = 50265600000.

The previous prime is 128838040831. The next prime is 128838040847. The reversal of 128838040840 is 48040838821.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 16922367396 + 111915673444 = 130086^2 + 334538^2 .

It is not an unprimeable number, because it can be changed into a prime (128838040847) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9014500 + ... + 9028780.

Almost surely, 2^128838040840 is an apocalyptic number.

128838040840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128838040840 is an abundant number, since it is smaller than the sum of its proper divisors (168192711080).

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

128838040840 is a wasteful number, since it uses less digits than its factorization.

128838040840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19834 (or 19830 counting only the distinct ones).

The product of its (nonzero) digits is 393216, while the sum is 46.

The spelling of 128838040840 in words is "one hundred twenty-eight billion, eight hundred thirty-eight million, forty thousand, eight hundred forty".