66439379 has 2 divisors, whose sum is σ = 66439380. Its totient is φ = 66439378.

The previous prime is 66439361. The next prime is 66439391. The reversal of 66439379 is 97393466.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66439379 - 2¹⁶ = 66373843 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66439339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33219689 + 33219690.

It is an arithmetic number, because the mean of its divisors is an integer number (33219690).

Almost surely, 2^66439379 is an apocalyptic number.

66439379 is a deficient number, since it is larger than the sum of its proper divisors (1).

66439379 is an equidigital number, since it uses as much as digits as its factorization.

66439379 is an evil number, because the sum of its binary digits is even.

The product of its digits is 734832, while the sum is 47.

The square root of 66439379 is about 8151.0354556952. The cubic root of 66439379 is about 405.0188052031.

The spelling of 66439379 in words is "sixty-six million, four hundred thirty-nine thousand, three hundred seventy-nine".