66636551 has 2 divisors, whose sum is σ = 66636552. Its totient is φ = 66636550.

The previous prime is 66636533. The next prime is 66636569. The reversal of 66636551 is 15563666.

It is a balanced prime because it is at equal distance from previous prime (66636533) and next prime (66636569).

It is a cyclic number.

It is not a de Polignac number, because 66636551 - 2⁶ = 66636487 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66686551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33318275 + 33318276.

It is an arithmetic number, because the mean of its divisors is an integer number (33318276).

Almost surely, 2^66636551 is an apocalyptic number.

66636551 is a deficient number, since it is larger than the sum of its proper divisors (1).

66636551 is an equidigital number, since it uses as much as digits as its factorization.

66636551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 97200, while the sum is 38.

The square root of 66636551 is about 8163.1214005428. The cubic root of 66636551 is about 405.4190673195.

The spelling of 66636551 in words is "sixty-six million, six hundred thirty-six thousand, five hundred fifty-one".