64378939 has 2 divisors, whose sum is σ = 64378940. Its totient is φ = 64378938.

The previous prime is 64378913. The next prime is 64378943. The reversal of 64378939 is 93987346.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 64378939 - 2⁵ = 64378907 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 64378892 and 64378901.

It is not a weakly prime, because it can be changed into another prime (64378339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32189469 + 32189470.

It is an arithmetic number, because the mean of its divisors is an integer number (32189470).

Almost surely, 2^64378939 is an apocalyptic number.

64378939 is a deficient number, since it is larger than the sum of its proper divisors (1).

64378939 is an equidigital number, since it uses as much as digits as its factorization.

64378939 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 979776, while the sum is 49.

The square root of 64378939 is about 8023.6487335875. The cubic root of 64378939 is about 400.7879032522.

It can be divided in two parts, 6437 and 8939, that added together give a square (15376 = 124²).

The spelling of 64378939 in words is "sixty-four million, three hundred seventy-eight thousand, nine hundred thirty-nine".