66953647 has 2 divisors, whose sum is σ = 66953648. Its totient is φ = 66953646.

The previous prime is 66953641. The next prime is 66953651. The reversal of 66953647 is 74635966.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66953647 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66953597 and 66953606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66953641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33476823 + 33476824.

It is an arithmetic number, because the mean of its divisors is an integer number (33476824).

Almost surely, 2^66953647 is an apocalyptic number.

66953647 is a deficient number, since it is larger than the sum of its proper divisors (1).

66953647 is an equidigital number, since it uses as much as digits as its factorization.

66953647 is an evil number, because the sum of its binary digits is even.

The product of its digits is 816480, while the sum is 46.

The square root of 66953647 is about 8182.5208218495. The cubic root of 66953647 is about 406.0611242874.

It can be divided in two parts, 66953 and 647, that added together give a square (67600 = 260²).

The spelling of 66953647 in words is "sixty-six million, nine hundred fifty-three thousand, six hundred forty-seven".