42405731 has 2 divisors, whose sum is σ = 42405732. Its totient is φ = 42405730.

The previous prime is 42405709. The next prime is 42405751. The reversal of 42405731 is 13750424.

42405731 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42405731 is a prime.

It is a super-2 number, since 2×42405731² = 3596492043288722, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42405731.

It is not a weakly prime, because it can be changed into another prime (42405751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21202865 + 21202866.

It is an arithmetic number, because the mean of its divisors is an integer number (21202866).

Almost surely, 2^42405731 is an apocalyptic number.

42405731 is a deficient number, since it is larger than the sum of its proper divisors (1).

42405731 is an equidigital number, since it uses as much as digits as its factorization.

42405731 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3360, while the sum is 26.

The square root of 42405731 is about 6511.9682892348. The cubic root of 42405731 is about 348.7183903555.

The spelling of 42405731 in words is "forty-two million, four hundred five thousand, seven hundred thirty-one".