42941981 has 2 divisors, whose sum is σ = 42941982. Its totient is φ = 42941980.

The previous prime is 42941971. The next prime is 42941999. The reversal of 42941981 is 18914924.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 33120025 + 9821956 = 5755^2 + 3134^2 .

It is a cyclic number.

It is not a de Polignac number, because 42941981 - 2⁶ = 42941917 is a prime.

It is a super-2 number, since 2×42941981² = 3688027464408722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42941971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21470990 + 21470991.

It is an arithmetic number, because the mean of its divisors is an integer number (21470991).

Almost surely, 2^42941981 is an apocalyptic number.

It is an amenable number.

42941981 is a deficient number, since it is larger than the sum of its proper divisors (1).

42941981 is an equidigital number, since it uses as much as digits as its factorization.

42941981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20736, while the sum is 38.

The square root of 42941981 is about 6553.0131237470. The cubic root of 42941981 is about 350.1821663949.

The spelling of 42941981 in words is "forty-two million, nine hundred forty-one thousand, nine hundred eighty-one".