128738420 has 24 divisors (see below), whose sum is σ = 274057224. Its totient is φ = 50789376.

The previous prime is 128738417. The next prime is 128738543. The reversal of 128738420 is 24837821.

It can be written as a sum of positive squares in 4 ways, for example, as 21325924 + 107412496 = 4618^2 + 10364^2 .

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, 42629 + ... + 45548.

It is an arithmetic number, because the mean of its divisors is an integer number (11419051).

Almost surely, 2^128738420 is an apocalyptic number.

128738420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128738420 is an abundant number, since it is smaller than the sum of its proper divisors (145318804).

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

128738420 is a wasteful number, since it uses less digits than its factorization.

128738420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88259 (or 88257 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 35.

The square root of 128738420 is about 11346.2954306681. The cubic root of 128738420 is about 504.9356778514.

It can be divided in two parts, 1287 and 38420, that multiplied together give a triangular number (49446540 = T₉₉₄₄).

The spelling of 128738420 in words is "one hundred twenty-eight million, seven hundred thirty-eight thousand, four hundred twenty".