661061 has 2 divisors, whose sum is σ = 661062. Its totient is φ = 661060.

The previous prime is 661049. The next prime is 661091. The reversal of 661061 is 160166.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 630436 + 30625 = 794^2 + 175^2 .

It is a cyclic number.

It is not a de Polignac number, because 661061 - 2¹⁸ = 398917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330530 + 330531.

It is an arithmetic number, because the mean of its divisors is an integer number (330531).

2⁶⁶¹⁰⁶¹ is an apocalyptic number.

It is an amenable number.

661061 is a deficient number, since it is larger than the sum of its proper divisors (1).

661061 is an equidigital number, since it uses as much as digits as its factorization.

661061 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 661061 is about 813.0565785971. The cubic root of 661061 is about 87.1125069312.

The spelling of 661061 in words is "six hundred sixty-one thousand, sixty-one".