385987661 has 2 divisors, whose sum is σ = 385987662. Its totient is φ = 385987660.

The previous prime is 385987643. The next prime is 385987697. The reversal of 385987661 is 166789583.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 224850025 + 161137636 = 14995^2 + 12694^2 .

It is a cyclic number.

It is not a de Polignac number, because 385987661 - 2¹⁰ = 385986637 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (385987631) 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, 192993830 + 192993831.

It is an arithmetic number, because the mean of its divisors is an integer number (192993831).

Almost surely, 2^385987661 is an apocalyptic number.

It is an amenable number.

385987661 is a deficient number, since it is larger than the sum of its proper divisors (1).

385987661 is an equidigital number, since it uses as much as digits as its factorization.

385987661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2177280, while the sum is 53.

The square root of 385987661 is about 19646.5686825970. The cubic root of 385987661 is about 728.1001835771.

The spelling of 385987661 in words is "three hundred eighty-five million, nine hundred eighty-seven thousand, six hundred sixty-one".