128428429 has 8 divisors (see below), whose sum is σ = 135620640. Its totient is φ = 121279536.

The previous prime is 128428411. The next prime is 128428439. The reversal of 128428429 is 924824821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 128428429 - 2⁵ = 128428397 is a prime.

It is a super-2 number, since 2×128428429² = 32987722750816082, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 128428391 and 128428400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128428439) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4639 + ... + 16684.

It is an arithmetic number, because the mean of its divisors is an integer number (16952580).

Almost surely, 2^128428429 is an apocalyptic number.

128428429 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

128428429 is a deficient number, since it is larger than the sum of its proper divisors (7192211).

128428429 is a wasteful number, since it uses less digits than its factorization.

128428429 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21659.

The product of its digits is 73728, while the sum is 40.

The square root of 128428429 is about 11332.6267475815. The cubic root of 128428429 is about 504.5300716168.

The spelling of 128428429 in words is "one hundred twenty-eight million, four hundred twenty-eight thousand, four hundred twenty-nine".