42740981 has 2 divisors, whose sum is σ = 42740982. Its totient is φ = 42740980.

The previous prime is 42740963. The next prime is 42740993. The reversal of 42740981 is 18904724.

42740981 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 can be written as a sum of positive squares in only one way, i.e., 39262756 + 3478225 = 6266^2 + 1865^2 .

It is a cyclic number.

It is not a de Polignac number, because 42740981 - 2⁶ = 42740917 is a prime.

It is a super-2 number, since 2×42740981² = 3653582913684722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42740911) 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, 21370490 + 21370491.

It is an arithmetic number, because the mean of its divisors is an integer number (21370491).

Almost surely, 2^42740981 is an apocalyptic number.

It is an amenable number.

42740981 is a deficient number, since it is larger than the sum of its proper divisors (1).

42740981 is an equidigital number, since it uses as much as digits as its factorization.

42740981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 42740981 is about 6537.6586787626. The cubic root of 42740981 is about 349.6349418171.

The spelling of 42740981 in words is "forty-two million, seven hundred forty thousand, nine hundred eighty-one".