38530781 has 2 divisors, whose sum is σ = 38530782. Its totient is φ = 38530780.

The previous prime is 38530771. The next prime is 38530813. The reversal of 38530781 is 18703583.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38019556 + 511225 = 6166^2 + 715^2 .

It is an emirp because it is prime and its reverse (18703583) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-38530781 is a prime.

It is a super-2 number, since 2×38530781² = 2969242168939922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (38530771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19265390 + 19265391.

It is an arithmetic number, because the mean of its divisors is an integer number (19265391).

Almost surely, 2^38530781 is an apocalyptic number.

It is an amenable number.

38530781 is a deficient number, since it is larger than the sum of its proper divisors (1).

38530781 is an equidigital number, since it uses as much as digits as its factorization.

38530781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 38530781 is about 6207.3167310844. The cubic root of 38530781 is about 337.7556354953.

The spelling of 38530781 in words is "thirty-eight million, five hundred thirty thousand, seven hundred eighty-one".