206148781 has 2 divisors, whose sum is σ = 206148782. Its totient is φ = 206148780.

The previous prime is 206148763. The next prime is 206148799. The reversal of 206148781 is 187841602.

It is a balanced prime because it is at equal distance from previous prime (206148763) and next prime (206148799).

It can be written as a sum of positive squares in only one way, i.e., 183738025 + 22410756 = 13555^2 + 4734^2 .

It is a cyclic number.

It is not a de Polignac number, because 206148781 - 2¹⁵ = 206116013 is a prime.

It is a super-2 number, since 2×206148781² = 84994639815571922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 206148781.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206148881) 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, 103074390 + 103074391.

It is an arithmetic number, because the mean of its divisors is an integer number (103074391).

Almost surely, 2^206148781 is an apocalyptic number.

It is an amenable number.

206148781 is a deficient number, since it is larger than the sum of its proper divisors (1).

206148781 is an equidigital number, since it uses as much as digits as its factorization.

It is an anagram of its base 9 representation: 206148781 = (470812861)₉.

206148781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21504, while the sum is 37.

The square root of 206148781 is about 14357.8821906296. The cubic root of 206148781 is about 590.7362072766.

The spelling of 206148781 in words is "two hundred six million, one hundred forty-eight thousand, seven hundred eighty-one".