66085531 has 2 divisors, whose sum is σ = 66085532. Its totient is φ = 66085530.

The previous prime is 66085493. The next prime is 66085549. The reversal of 66085531 is 13558066.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66085531 - 2¹³ = 66077339 is a prime.

It is a super-2 number, since 2×66085531² = 8734594815103922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66085561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33042765 + 33042766.

It is an arithmetic number, because the mean of its divisors is an integer number (33042766).

Almost surely, 2^66085531 is an apocalyptic number.

66085531 is a deficient number, since it is larger than the sum of its proper divisors (1).

66085531 is an equidigital number, since it uses as much as digits as its factorization.

66085531 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21600, while the sum is 34.

The square root of 66085531 is about 8129.3007694389. The cubic root of 66085531 is about 404.2984980698.

The spelling of 66085531 in words is "sixty-six million, eighty-five thousand, five hundred thirty-one".