66553247 has 2 divisors, whose sum is σ = 66553248. Its totient is φ = 66553246.

The previous prime is 66553217. The next prime is 66553259. The reversal of 66553247 is 74235566.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66553247 - 2¹⁴ = 66536863 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66553247.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66553217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33276623 + 33276624.

It is an arithmetic number, because the mean of its divisors is an integer number (33276624).

Almost surely, 2^66553247 is an apocalyptic number.

66553247 is a deficient number, since it is larger than the sum of its proper divisors (1).

66553247 is an equidigital number, since it uses as much as digits as its factorization.

66553247 is an evil number, because the sum of its binary digits is even.

The product of its digits is 151200, while the sum is 38.

The square root of 66553247 is about 8158.0173449190. The cubic root of 66553247 is about 405.2500554046.

The spelling of 66553247 in words is "sixty-six million, five hundred fifty-three thousand, two hundred forty-seven".