1006781 has 2 divisors, whose sum is σ = 1006782. Its totient is φ = 1006780.

The previous prime is 1006769. The next prime is 1006783. The reversal of 1006781 is 1876001.

1006781 = 709² + 710².

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 504100 + 502681 = 710^2 + 709^2 .

It is a cyclic number.

It is not a de Polignac number, because 1006781 - 2¹⁴ = 990397 is a prime.

It is a super-2 number, since 2×1006781² = 2027215963922, which contains 22 as substring.

Together with 1006783, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1006783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 503390 + 503391.

It is an arithmetic number, because the mean of its divisors is an integer number (503391).

2^1006781 is an apocalyptic number.

1006781 is the 710-th centered square number.

It is an amenable number.

1006781 is a deficient number, since it is larger than the sum of its proper divisors (1).

1006781 is an equidigital number, since it uses as much as digits as its factorization.

1006781 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 1006781 is about 1003.3847716604. The cubic root of 1006781 is about 100.2255243387.

The spelling of 1006781 in words is "one million, six thousand, seven hundred eighty-one".