38773781 has 2 divisors, whose sum is σ = 38773782. Its totient is φ = 38773780.

The previous prime is 38773769. The next prime is 38773789. The reversal of 38773781 is 18737783.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 36493681 + 2280100 = 6041^2 + 1510^2 .

It is an emirp because it is prime and its reverse (18737783) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 38773781 - 2⁶ = 38773717 is a prime.

It is a super-2 number, since 2×38773781² = 3006812186071922, 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 (38773789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19386890 + 19386891.

It is an arithmetic number, because the mean of its divisors is an integer number (19386891).

Almost surely, 2^38773781 is an apocalyptic number.

It is an amenable number.

38773781 is a deficient number, since it is larger than the sum of its proper divisors (1).

38773781 is an equidigital number, since it uses as much as digits as its factorization.

38773781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 197568, while the sum is 44.

The square root of 38773781 is about 6226.8596419062. The cubic root of 38773781 is about 338.4641831445.

The spelling of 38773781 in words is "thirty-eight million, seven hundred seventy-three thousand, seven hundred eighty-one".