3616780781 has 2 divisors, whose sum is σ = 3616780782. Its totient is φ = 3616780780.

The previous prime is 3616780729. The next prime is 3616780799. The reversal of 3616780781 is 1870876163.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3369222025 + 247558756 = 58045^2 + 15734^2 .

It is a cyclic number.

It is not a de Polignac number, because 3616780781 - 2¹⁴ = 3616764397 is a prime.

It is a super-2 number, since 2×3616780781² = 26162206435621939922, which contains 22 as substring.

It is a Sophie Germain 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 (3616780711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1808390390 + 1808390391.

It is an arithmetic number, because the mean of its divisors is an integer number (1808390391).

Almost surely, 2^3616780781 is an apocalyptic number.

It is an amenable number.

3616780781 is a deficient number, since it is larger than the sum of its proper divisors (1).

3616780781 is an equidigital number, since it uses as much as digits as its factorization.

3616780781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 338688, while the sum is 47.

The square root of 3616780781 is about 60139.6772605241. The cubic root of 3616780781 is about 1534.9965206979.

The spelling of 3616780781 in words is "three billion, six hundred sixteen million, seven hundred eighty thousand, seven hundred eighty-one".