42662821 has 2 divisors, whose sum is σ = 42662822. Its totient is φ = 42662820.

The previous prime is 42662819. The next prime is 42662833. The reversal of 42662821 is 12826624.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 37761025 + 4901796 = 6145^2 + 2214^2 .

It is a cyclic number.

It is not a de Polignac number, because 42662821 - 2¹ = 42662819 is a prime.

Together with 42662819, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42662801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21331410 + 21331411.

It is an arithmetic number, because the mean of its divisors is an integer number (21331411).

Almost surely, 2^42662821 is an apocalyptic number.

It is an amenable number.

42662821 is a deficient number, since it is larger than the sum of its proper divisors (1).

42662821 is an equidigital number, since it uses as much as digits as its factorization.

42662821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9216, while the sum is 31.

The square root of 42662821 is about 6531.6782682554. The cubic root of 42662821 is about 349.4216871439.

The spelling of 42662821 in words is "forty-two million, six hundred sixty-two thousand, eight hundred twenty-one".