406681549 has 2 divisors, whose sum is σ = 406681550. Its totient is φ = 406681548.

The previous prime is 406681523. The next prime is 406681589. The reversal of 406681549 is 945186604.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 314175625 + 92505924 = 17725^2 + 9618^2 .

It is a cyclic number.

It is not a de Polignac number, because 406681549 - 2¹⁷ = 406550477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (406681589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 203340774 + 203340775.

It is an arithmetic number, because the mean of its divisors is an integer number (203340775).

Almost surely, 2^406681549 is an apocalyptic number.

It is an amenable number.

406681549 is a deficient number, since it is larger than the sum of its proper divisors (1).

406681549 is an equidigital number, since it uses as much as digits as its factorization.

406681549 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 207360, while the sum is 43.

The square root of 406681549 is about 20166.3469423691. The cubic root of 406681549 is about 740.8861729562.

The spelling of 406681549 in words is "four hundred six million, six hundred eighty-one thousand, five hundred forty-nine".