6201781 has 2 divisors, whose sum is σ = 6201782. Its totient is φ = 6201780.

The previous prime is 6201739. The next prime is 6201799. The reversal of 6201781 is 1871026.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6200100 + 1681 = 2490^2 + 41^2 .

It is a cyclic number.

It is not a de Polignac number, because 6201781 - 2¹⁵ = 6169013 is a prime.

It is a super-2 number, since 2×6201781² = 76924175143922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6201731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3100890 + 3100891.

It is an arithmetic number, because the mean of its divisors is an integer number (3100891).

Almost surely, 2^6201781 is an apocalyptic number.

It is an amenable number.

6201781 is a deficient number, since it is larger than the sum of its proper divisors (1).

6201781 is an equidigital number, since it uses as much as digits as its factorization.

6201781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 672, while the sum is 25.

The square root of 6201781 is about 2490.3375273244. The cubic root of 6201781 is about 183.7266439532.

It can be divided in two parts, 620 and 1781, that added together give a 4-th power (2401 = 7⁴).

The spelling of 6201781 in words is "six million, two hundred one thousand, seven hundred eighty-one".