42855661 has 2 divisors, whose sum is σ = 42855662. Its totient is φ = 42855660.

The previous prime is 42855581. The next prime is 42855677. The reversal of 42855661 is 16655824.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23097636 + 19758025 = 4806^2 + 4445^2 .

It is a cyclic number.

It is not a de Polignac number, because 42855661 - 2⁹ = 42855149 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42855661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42853661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21427830 + 21427831.

It is an arithmetic number, because the mean of its divisors is an integer number (21427831).

Almost surely, 2^42855661 is an apocalyptic number.

It is an amenable number.

42855661 is a deficient number, since it is larger than the sum of its proper divisors (1).

42855661 is an equidigital number, since it uses as much as digits as its factorization.

42855661 is an evil number, because the sum of its binary digits is even.

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

The square root of 42855661 is about 6546.4235273926. The cubic root of 42855661 is about 349.9473689568.

The spelling of 42855661 in words is "forty-two million, eight hundred fifty-five thousand, six hundred sixty-one".