66381011 has 2 divisors, whose sum is σ = 66381012. Its totient is φ = 66381010.

The previous prime is 66380969. The next prime is 66381031. The reversal of 66381011 is 11018366.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66381011 - 2⁶ = 66380947 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (66381031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33190505 + 33190506.

It is an arithmetic number, because the mean of its divisors is an integer number (33190506).

Almost surely, 2^66381011 is an apocalyptic number.

66381011 is a deficient number, since it is larger than the sum of its proper divisors (1).

66381011 is an equidigital number, since it uses as much as digits as its factorization.

66381011 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 66381011 is about 8147.4542649836. The cubic root of 66381011 is about 404.9001654040.

Adding to 66381011 its reverse (11018366), we get a palindrome (77399377).

The spelling of 66381011 in words is "sixty-six million, three hundred eighty-one thousand, eleven".