66503257 has 2 divisors, whose sum is σ = 66503258. Its totient is φ = 66503256.

The previous prime is 66503251. The next prime is 66503263. The reversal of 66503257 is 75230566.

It is a balanced prime because it is at equal distance from previous prime (66503251) and next prime (66503263).

It can be written as a sum of positive squares in only one way, i.e., 64256256 + 2247001 = 8016^2 + 1499^2 .

It is a cyclic number.

It is not a de Polignac number, because 66503257 - 2¹¹ = 66501209 is a prime.

It is not a weakly prime, because it can be changed into another prime (66503251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33251628 + 33251629.

It is an arithmetic number, because the mean of its divisors is an integer number (33251629).

Almost surely, 2^66503257 is an apocalyptic number.

It is an amenable number.

66503257 is a deficient number, since it is larger than the sum of its proper divisors (1).

66503257 is an equidigital number, since it uses as much as digits as its factorization.

66503257 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 37800, while the sum is 34.

The square root of 66503257 is about 8154.9529121878. The cubic root of 66503257 is about 405.1485651166.

The spelling of 66503257 in words is "sixty-six million, five hundred three thousand, two hundred fifty-seven".