42006681 has 12 divisors (see below), whose sum is σ = 62923952. Its totient is φ = 28004292.

The previous prime is 42006659. The next prime is 42006683. The reversal of 42006681 is 18660024.

It is not a de Polignac number, because 42006681 - 2⁶ = 42006617 is a prime.

It is a super-2 number, since 2×42006681² = 3529122497271522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42006683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 86191 + ... + 86676.

Almost surely, 2^42006681 is an apocalyptic number.

It is an amenable number.

42006681 is a deficient number, since it is larger than the sum of its proper divisors (20917271).

42006681 is an equidigital number, since it uses as much as digits as its factorization.

42006681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172882 (or 172870 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 42006681 is about 6481.2561282517. The cubic root of 42006681 is about 347.6210947289.

The spelling of 42006681 in words is "forty-two million, six thousand, six hundred eighty-one".