64381819 has 2 divisors, whose sum is σ = 64381820. Its totient is φ = 64381818.

The previous prime is 64381789. The next prime is 64381829. The reversal of 64381819 is 91818346.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 64381819 - 2⁵ = 64381787 is a prime.

It is a super-2 number, since 2×64381819² = 8290037235497522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (64381829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32190909 + 32190910.

It is an arithmetic number, because the mean of its divisors is an integer number (32190910).

Almost surely, 2^64381819 is an apocalyptic number.

64381819 is a deficient number, since it is larger than the sum of its proper divisors (1).

64381819 is an equidigital number, since it uses as much as digits as its factorization.

64381819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41472, while the sum is 40.

The square root of 64381819 is about 8023.8282010522. The cubic root of 64381819 is about 400.7938795956.

The spelling of 64381819 in words is "sixty-four million, three hundred eighty-one thousand, eight hundred nineteen".