66705761 has 2 divisors, whose sum is σ = 66705762. Its totient is φ = 66705760.

The previous prime is 66705703. The next prime is 66705781. The reversal of 66705761 is 16750766.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 37210000 + 29495761 = 6100^2 + 5431^2 .

It is a cyclic number.

It is not a de Polignac number, because 66705761 - 2⁶ = 66705697 is a prime.

It is a Chen prime.

It is equal to p_3935486 and since 66705761 and 3935486 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (66705781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33352880 + 33352881.

It is an arithmetic number, because the mean of its divisors is an integer number (33352881).

Almost surely, 2^66705761 is an apocalyptic number.

It is an amenable number.

66705761 is a deficient number, since it is larger than the sum of its proper divisors (1).

66705761 is an equidigital number, since it uses as much as digits as its factorization.

66705761 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 52920, while the sum is 38.

The square root of 66705761 is about 8167.3594876190. The cubic root of 66705761 is about 405.5593774276.

The spelling of 66705761 in words is "sixty-six million, seven hundred five thousand, seven hundred sixty-one".