42556861 has 2 divisors, whose sum is σ = 42556862. Its totient is φ = 42556860.

The previous prime is 42556853. The next prime is 42556873. The reversal of 42556861 is 16865524.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38675961 + 3880900 = 6219^2 + 1970^2 .

It is a cyclic number.

It is not a de Polignac number, because 42556861 - 2³ = 42556853 is a prime.

It is a super-2 number, since 2×42556861² = 3622172836346642, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 42556861.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42556841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21278430 + 21278431.

It is an arithmetic number, because the mean of its divisors is an integer number (21278431).

Almost surely, 2^42556861 is an apocalyptic number.

It is an amenable number.

42556861 is a deficient number, since it is larger than the sum of its proper divisors (1).

42556861 is an equidigital number, since it uses as much as digits as its factorization.

42556861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 57600, while the sum is 37.

The square root of 42556861 is about 6523.5619871356. The cubic root of 42556861 is about 349.1321656061.

The spelling of 42556861 in words is "forty-two million, five hundred fifty-six thousand, eight hundred sixty-one".