66078497 has 2 divisors, whose sum is σ = 66078498. Its totient is φ = 66078496.

The previous prime is 66078491. The next prime is 66078499. The reversal of 66078497 is 79487066.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55115776 + 10962721 = 7424^2 + 3311^2 .

It is a cyclic number.

It is not a de Polignac number, because 66078497 - 2²⁴ = 49301281 is a prime.

Together with 66078499, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66078491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33039248 + 33039249.

It is an arithmetic number, because the mean of its divisors is an integer number (33039249).

Almost surely, 2^66078497 is an apocalyptic number.

It is an amenable number.

66078497 is a deficient number, since it is larger than the sum of its proper divisors (1).

66078497 is an equidigital number, since it uses as much as digits as its factorization.

66078497 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 508032, while the sum is 47.

The square root of 66078497 is about 8128.8681253911. The cubic root of 66078497 is about 404.2841533436.

The spelling of 66078497 in words is "sixty-six million, seventy-eight thousand, four hundred ninety-seven".