36820781 has 2 divisors, whose sum is σ = 36820782. Its totient is φ = 36820780.

The previous prime is 36820753. The next prime is 36820799. The reversal of 36820781 is 18702863.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 34692100 + 2128681 = 5890^2 + 1459^2 .

It is an emirp because it is prime and its reverse (18702863) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 36820781 - 2⁶ = 36820717 is a prime.

It is a super-2 number, since 2×36820781² = 2711539826899922, 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 (36820741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18410390 + 18410391.

It is an arithmetic number, because the mean of its divisors is an integer number (18410391).

Almost surely, 2^36820781 is an apocalyptic number.

It is an amenable number.

36820781 is a deficient number, since it is larger than the sum of its proper divisors (1).

36820781 is an equidigital number, since it uses as much as digits as its factorization.

36820781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 36820781 is about 6068.0129367034. The cubic root of 36820781 is about 332.6832984100.

The spelling of 36820781 in words is "thirty-six million, eight hundred twenty thousand, seven hundred eighty-one".