128920237 has 4 divisors (see below), whose sum is σ = 128969820. Its totient is φ = 128870656.

The previous prime is 128920229. The next prime is 128920243. The reversal of 128920237 is 732029821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 732029821 = 2287 ⋅320083.

It can be written as a sum of positive squares in 2 ways, for example, as 65383396 + 63536841 = 8086^2 + 7971^2 .

It is a cyclic number.

It is not a de Polignac number, because 128920237 - 2³ = 128920229 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128920217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20662 + ... + 26167.

It is an arithmetic number, because the mean of its divisors is an integer number (32242455).

Almost surely, 2^128920237 is an apocalyptic number.

It is an amenable number.

128920237 is a deficient number, since it is larger than the sum of its proper divisors (49583).

128920237 is an equidigital number, since it uses as much as digits as its factorization.

128920237 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49582.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 128920237 is about 11354.3047783649. The cubic root of 128920237 is about 505.1732725672.

The spelling of 128920237 in words is "one hundred twenty-eight million, nine hundred twenty thousand, two hundred thirty-seven".