385661 has 2 divisors, whose sum is σ = 385662. Its totient is φ = 385660.

The previous prime is 385657. The next prime is 385663. The reversal of 385661 is 166583.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 383161 + 2500 = 619^2 + 50^2 .

It is a cyclic number.

It is not a de Polignac number, because 385661 - 2² = 385657 is a prime.

Together with 385663, 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 (385663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 192830 + 192831.

It is an arithmetic number, because the mean of its divisors is an integer number (192831).

2³⁸⁵⁶⁶¹ is an apocalyptic number.

It is an amenable number.

385661 is a deficient number, since it is larger than the sum of its proper divisors (1).

385661 is an equidigital number, since it uses as much as digits as its factorization.

385661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4320, while the sum is 29.

The square root of 385661 is about 621.0161028508. The cubic root of 385661 is about 72.7894728770.

The spelling of 385661 in words is "three hundred eighty-five thousand, six hundred sixty-one".