16000781 has 2 divisors, whose sum is σ = 16000782. Its totient is φ = 16000780.

The previous prime is 16000769. The next prime is 16000799. The reversal of 16000781 is 18700061.

16000781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14478025 + 1522756 = 3805^2 + 1234^2 .

It is an emirp because it is prime and its reverse (18700061) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16000781 - 2¹⁰ = 15999757 is a prime.

It is a super-2 number, since 2×16000781² = 512049985219922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16000711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8000390 + 8000391.

It is an arithmetic number, because the mean of its divisors is an integer number (8000391).

Almost surely, 2^16000781 is an apocalyptic number.

It is an amenable number.

16000781 is a deficient number, since it is larger than the sum of its proper divisors (1).

16000781 is an equidigital number, since it uses as much as digits as its factorization.

16000781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 336, while the sum is 23.

The square root of 16000781 is about 4000.0976238087. The cubic root of 16000781 is about 251.9883099053.

The spelling of 16000781 in words is "sixteen million, seven hundred eighty-one", and thus it is an aban number.