42128491 has 16 divisors (see below), whose sum is σ = 45552640. Its totient is φ = 38841120.

The previous prime is 42128477. The next prime is 42128549. The reversal of 42128491 is 19482124.

It is a cyclic number.

It is not a de Polignac number, because 42128491 - 2⁹ = 42127979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42128791) 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, 188806 + ... + 189028.

It is an arithmetic number, because the mean of its divisors is an integer number (2847040).

Almost surely, 2^42128491 is an apocalyptic number.

42128491 is a deficient number, since it is larger than the sum of its proper divisors (3424149).

42128491 is a wasteful number, since it uses less digits than its factorization.

42128491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 466.

The product of its digits is 4608, while the sum is 31.

The square root of 42128491 is about 6490.6464238934. The cubic root of 42128491 is about 347.9567783331.

The spelling of 42128491 in words is "forty-two million, one hundred twenty-eight thousand, four hundred ninety-one".