661267 has 2 divisors, whose sum is σ = 661268. Its totient is φ = 661266.

The previous prime is 661259. The next prime is 661321. The reversal of 661267 is 762166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 661267 - 2³ = 661259 is a prime.

It is not a weakly prime, because it can be changed into another prime (661217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330633 + 330634.

It is an arithmetic number, because the mean of its divisors is an integer number (330634).

2⁶⁶¹²⁶⁷ is an apocalyptic number.

661267 is a deficient number, since it is larger than the sum of its proper divisors (1).

661267 is an equidigital number, since it uses as much as digits as its factorization.

661267 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3024, while the sum is 28.

The square root of 661267 is about 813.1832511802. The cubic root of 661267 is about 87.1215546655.

The spelling of 661267 in words is "six hundred sixty-one thousand, two hundred sixty-seven".