42128831 has 2 divisors, whose sum is σ = 42128832. Its totient is φ = 42128830.

The previous prime is 42128819. The next prime is 42128869. The reversal of 42128831 is 13882124.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42128831 - 2²² = 37934527 is a prime.

It is a super-2 number, since 2×42128831² = 3549676802853122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 42128794 and 42128803.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42128131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21064415 + 21064416.

It is an arithmetic number, because the mean of its divisors is an integer number (21064416).

Almost surely, 2^42128831 is an apocalyptic number.

42128831 is a deficient number, since it is larger than the sum of its proper divisors (1).

42128831 is an equidigital number, since it uses as much as digits as its factorization.

42128831 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3072, while the sum is 29.

The square root of 42128831 is about 6490.6726153766. The cubic root of 42128831 is about 347.9577143979.

The spelling of 42128831 in words is "forty-two million, one hundred twenty-eight thousand, eight hundred thirty-one".