42773821 has 2 divisors, whose sum is σ = 42773822. Its totient is φ = 42773820.

The previous prime is 42773791. The next prime is 42773833. The reversal of 42773821 is 12837724.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 32604100 + 10169721 = 5710^2 + 3189^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42773821 is a prime.

It is equal to p_2591728 and since 42773821 and 2591728 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42773881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21386910 + 21386911.

It is an arithmetic number, because the mean of its divisors is an integer number (21386911).

Almost surely, 2^42773821 is an apocalyptic number.

It is an amenable number.

42773821 is a deficient number, since it is larger than the sum of its proper divisors (1).

42773821 is an equidigital number, since it uses as much as digits as its factorization.

42773821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18816, while the sum is 34.

The square root of 42773821 is about 6540.1697990190. The cubic root of 42773821 is about 349.7244661390.

The spelling of 42773821 in words is "forty-two million, seven hundred seventy-three thousand, eight hundred twenty-one".